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When iconic QBs depart, it often gets ugly

History could offer roadmap to how Tom Brady’s exit from Patriots may go

Photo Illustration by Joe Moore

Many elite-level quarterbacks before Tom Brady have faced challenging circumstances when the end of their playing days arrives.

Jimmy Garappolo’s arrival may have been a jolt to some that the Patriots are now planning for the end of Tom Brady’s time as their starting quarterback.

It likely won’t come this year. And it may not happen next year or the year after. But whenever it occurs, Patriots fans should take note now: These things rarely end on a positive note.

Continue reading below

The recent history of breakups with elite quarterbacks has too often been messy — and has often resulted in an extended search for a replacement.

A look through those departures could offer a road map to how Brady’s exit from the Patriots may go:

JOE MONTANA

How he exited: Surpassed on depth chart by Steve Young and was traded by 49ers to Kansas City in 1993.

Age when he left: 36

Parting synopsis: Navigating two Hall of Famers who are only 5 years apart in age is bound to be difficult, and it was for the 49ers with Montana and Young.

Joe Montana became the symbol of the 49ers when he led the team to four Super Bowls titles.

ABC photo

Joe Montana became the symbol of the 49ers when he led the team to four Super Bowls titles.

Montana was already a two-time Super Bowl MVP at age 30 when the 49ers acquired Young in 1987 from Tampa. Young, chosen No. 1 overall in the 1984 supplemental draft, was undervalued on an awful Buccaneers team.

There was no quarterback controversy when Young, then 25, arrived. For several years he played sporadically in relief of Montana, but enough that whispers flew about whether he deserved to start. Yet the man he was relieving was in the midst of leading the 49ers to two more Super Bowls titles in the 1988 and 1989 seasons, and he was named NFL MVP in 1989.

“I felt I had to make sure [he] stayed over there watching me as long as possible,” Montana said last year. “But it’s a competitive relationship . . . I didn’t feel bad for him.”

Montana’s chokehold on the starting job ended in 1991 when an injury suffered in the previous season’s NFC title game loss kept him out for the year. Young seized the job, and it did not seem like there would be a roster big enough for both him and Montana at that point.

“I’m not going to accept No. 2 status,” Young said in May 1992. “That would be like running in the Kentucky Derby and then going back to run with the trotters at Yonkers. It’s illogical.”

In the 1992 season, with Montana still sidelined, Young raised his game again, leading the 49ers to a 14-2 mark and winning the NFL MVP award. Montana actually did come back in the season’s final game and played well in mop-up duty, but the roles were reversed at this point. The 49ers had two MVP quarterbacks, and it was smarter for them to bet on the younger one (Montana was 36, Young was 31).

That wasn’t going to work for Montana, just three years removed from his own MVP award. He asked for a trade and was dealt to Kansas City, where he played two quality seasons (losing to the Bills in the AFC title game during the 1993 season) but never reached the Super Bowl again.

Young played seven more seasons for the 49ers and was named NFL MVP and Super Bowl MVP during the 1994 season when the 49ers won another crown.

Steve Young went on to win Super Bowl XXIX for the 49ers, while Montana never again reached the final game after arriving in Kansas City.

Reuters, Getty photos

Steve Young went on to win Super Bowl XXIX for the 49ers, while Montana never again reached the final game after arriving in Kansas City.

Footnote: The 49ers had to go through the process of replacing an iconic quarterback yet again in the 1999 season when Young was forced out by a concussion and subsequently retired. They had signed CFL standout Jeff Garcia as a backup, and he blossomed into a Pro Bowl quarterback. The 49ers drafted two quarterbacks in 2000 (Giovanni Carmazzi and Tim Rattay), but Garcia ultimately won the job and had the 49ers back in the playoffs by 2001.

49ers’ record before and after Montana
W-LPlayoff berthsNotable
Final five years with Montana54-2632 Super Bowl wins
Five years after Montana58-2241 Super Bowl win
QBs drafted in five years before Montana’s departure
PlayerYearOverall pick
Darian Hagan1992242

JIM KELLY

How he exited: Retired in 1997 after 11 seasons in Buffalo.

Age when he left: 36

Parting synopsis: The Bills had a decent plan for replacing Kelly in turning to a young quarterback in their system. Todd Collins just couldn’t execute it.

Jim Kelly didn’t want to leave the game after the 1996 season, but ultimately chose to retire.

Kevin Higley/AP

Jim Kelly didn’t want to leave the game after the 1996 season, but ultimately chose to retire.

The Bills were preparing for Kelly’s eventual departure when they drafted Collins, a Walpole native, with the 45th overall pick in 1995.

Kelly, 35 at that point, ended up quarterbacking the Bills to two more 10-6 campaigns and two more playoff berths, but then retired after the 1996 season. He suffered a concussion in his final game and said he wanted to retire “with some dignity.”

So the Bills, who added veteran Billy Joe Hobert for depth after Kelly retired in early 1997, put their faith in Collins to replace the man who led Buffalo to an unprecedented four straight Super Bowls.

But Collins lasted just one disappointing year as the starter. The next winter, after Marv Levy retired and Wade Phillips replaced him as head coach, the Bills signed two potential starters in Rob Johnson and Doug Flutie.

Todd Collins lasted just one season as the starter in Buffalo after replacing Kelly.

AP

Todd Collins lasted just one season as the starter in Buffalo after replacing Kelly.

Johnson won the job in camp, but Flutie eventually emerged as the starter and led the Bills to the first of two straight playoff appearances. But the Bills brass never seemed satisfied with Flutie, and Johnson was named the starter in 2000 before Flutie was eventually cut.

It was an ominous move, as Flutie remains the last quarterback to lead the Bills to the playoffs. During the 14 seasons since, the Bills have swung from one starter to the next (11 in all) as they have endured the NFL’s longest playoff drought.

Bills' record before and after Kelly
W-LPlayoff berthsNotable
Final five years with Kelly50-3042 Super Bowl berths
Five years after Kelly38-4220 playoff wins
QBs drafted in five years before Kelly’s departure
PlayerYearOverall pick
Matt Rodgers1992335
Todd Collins199545

JOHN ELWAY

How he exited: Retired in 1999 after winning two straight Super Bowl titles with the Broncos.

Age when he left: 38

Parting synopsis: The Broncos, like the Bills with Kelly, ultimately committed to a young quarterback they drafted before Elway’s retirement. But Brian Griese did not live up to expectations.

John Elway left the field a champion when he opted to retire following his second straight Super Bowl win in 1999.

John Gaps III/AP

John Elway left the field a champion when he opted to retire following his second straight Super Bowl win in 1999.

Broncos coach Mike Shanahan’s plan to replace Elway teetered before he finally landed on Griese, whom he had drafted 91st overall a year earlier. Shanahan went into the season thinking he would start Bubby Brister, 37.

But he abandoned that plan during training camp when he demoted an ineffective Brister (who went 4-0 the previous year in relief of an injured Elway) in favor of Griese. Shanahan then wavered and recommitted (briefly) to Brister, only to turn back to Griese permanently before Brister (hampered by injury) could even get on the field.

Choosing Griese was the smart move. (Though it was a big blow for Brister, who said he had “earned the right to start opening day.”) Griese was the up-and-comer with a Hall of Fame bloodline from his dad, Bob. (And this was one year after Peyton Manning, another son of a prominent former quarterback, had been handed the keys to the Colts).

Griese had already absorbed Shanahan’s offense for a year and represented the best long-term option for Denver. (And Shanahan’s analysis on Brister was right. The journeyman would never start another game and was out of the NFL after the 2000 season.)

Brian Griese, right, lasted four seasons as the Broncos starter, but never was a suitable replacement for John Elway.

Bill Janscha/AP

Brian Griese, right, lasted four seasons as the Broncos starter, but never was a suitable replacement for John Elway.

Unfortunately for Shanahan and the Broncos, Griese just didn’t pan out. He started for four middling seasons, during which the Broncos made the playoffs only once. Shanahan signed Jake Plummer to be his starter in 2003, and when Plummer didn’t work out, he drafted Jay Cutler 11th overall in 2006 in pursuit of yet another Elway replacement.

Though he outlasted Shanahan in Denver, Cutler didn’t turn out to be the answer, either. And it was the inability of Shanahan (who had a .734 winning percentage with Elway) to win consistently without the Hall of Famer (he was .569 without him) that ultimately cost him his job in Denver.

It wasn’t until Elway returned, this time as the boss of the team’s football operations, that the Broncos finally found a suitable replacement in Manning.

Broncos' record before and after Elway
W-LPlayoff berthsNotable
Final five years with Elway54-2632 Super Bowl wins
Five years after Elway44-3620 playoff wins
QBs drafted in five years before Elway’s departure
PlayerYearOverall pick
Jeff Lewis1996100
Brian Griese199891

DAN MARINO

How he exited: Retired in 2000 after 17 seasons with Miami.

Age when he left: 38

Parting synopsis: The Dolphins have been looking for Marino’s successor seemingly ever since he left more than 14 years ago.

Damon Huard, right, started five games for the Dolphins in Dan Marino’s final season in 1999 and was in the running to replace him as the starter the next season.

Alan Diaz/AP

Damon Huard, right, started five games for the Dolphins in Dan Marino’s final season in 1999 and was in the running to replace him as the starter the next season.

Having Marino under center meant the Dolphins had next to no questions at quarterback for 17 years. But they have had an endless string of questions at quarterback in the 14 seasons since he retired.

The Dolphins went into the 2000 campaign expecting the tandem of Jay Fiedler and Damon Huard to compete for the starting job. In an ominous sign, Fielder got hurt early in camp and Huard, left alone to seize the job, still was not able to earn the nod.

Jay Fielder quarterbacked the Dolphins while they earned playoff spots in the first two seasons after Marino retired.

Marc Serota/Reuters

Jay Fielder quarterbacked the Dolphins while they earned playoff spots in the first two seasons after Marino retired.

Fielder was the first of 17 men to start at quarterback for the Dolphins over the next 13 seasons. It wasn’t until the past two years that the Dolphins found a quarterback to start every game over two consecutive seasons (Ryan Tannehill).

The Dolphins didn’t seem to think they needed to focus on finding a replacement for Marino through the draft. From 1991 to 2006, Miami never invested anything more than a sixth-round pick on a quarterback. They spent sixth-round picks on quarterbacks in 1998 (John Dutton) and 2001 (Josh Heupel), but neither ever played in an NFL game. In fact, none of their drafted signal callers from 1991 to 2006 ever threw a pass in the NFL.

The Dolphins entered the post-Marino era with a new defensive-minded head coach in Dave Wannstedt and a defense that had ranked fifth in the NFL the previous season. So their plan seemed to be that they would let the defense (stocked with Pro Bowlers like Brock Marion, Zach Thomas, Jason Taylor, Sam Madison, and Trace Armstrong) lead the team in lieu of a quarterback of Marino’s ilk. And it worked, for a short time.

The Dolphins made the playoffs with 11-5 records in 2000 and 2001 with defenses that ranked sixth and fifth, respectively, but never advanced past the divisional round. They sorely lacked an offense to complement their talented defense.

After 2001, the Dolphins would earn only one more playoff berth over the next 12 years as they moved from quarterback to quarterback.

Dolphins' record before and after Marino
W-LPlayoff berthsNotable
Final five years with Marino45-3542 playoff wins
Five years after Marino45-3521 playoff win
QBs drafted in five years before Marino’s departure
PlayerYearOverall pick
John Dutton1998172

TROY AIKMAN

How he exited: Retired in 2001 after 12 seasons in Dallas.

Age when he left: 34

Parting synopsis: When Aikman left, the Cowboys were unprepared and went into a tailspin.

After Troy Aikman retired, it would take the Cowboys almost a decade to win another playoff game.

Donna McWilliam/AP

After Troy Aikman retired, it would take the Cowboys almost a decade to win a playoff game.

If you were drawing up a plan on how you could most mess up replacing your franchise quarterback, it’s hard to envision a scenario that would top the Cowboys’.

The team cut Aikman after the 2000 season in a cost-cutting move that was meant to save them from a player who was no longer living up to his enormous contract and didn’t seem to recognize his days in the NFL were done. Aikman suffered two concussions in his final campaign, the second one ending his 2000 season after 11 games. Yet he still wanted to keep playing.

The Cowboys cut him before a $7 million bonus was due that would have extended his contract for several more years. But they had no real option for a next step.

At the time, it had been a decade since the Cowboys drafted a quarterback (Bill Musgrave, a fourth-rounder in 1991 who never played a game for Dallas). Aikman’s backup in his final season, 37-year-old Randall Cunningham, was cut after the 2000 season.

The Cowboys had two young quarterbacks in Anthony Wright (who started two games in 2000) and Clint Stoerner, but didn’t seem to have confidence in either. They signed veteran Tony Banks (who won a combined 15 games the three previous seasons for St. Louis and Baltimore) and proclaimed him the starter.

They also drafted Quincy Carter with the 53d overall pick (their first selection, since they had traded their first-round pick to Seattle in a deal for Joey Galloway) and proclaimed him the quarterback of the future.

So it’s no surprise that the hastily assembled plan didn’t pan out. Banks, whose commitment was in question, was cut by mid-August after just two preseason games. That left Carter (whom many saw as a reach as a second-round pick) as the starter.

Hampered by injuries and ineffectiveness, Carter started just eight games in his rookie season. The Cowboys stepped into an era where they seemed to be in a perpetual search for a quarterback. They started four signal callers in 2001 (Carter, Wright, Stoerner, and even Chargers castoff Ryan Leaf, whose final NFL action would come in his two starts for Dallas).

Quincy Carter was thrust into the role of Troy Aikman’s replacement and helped the Cowboys earn a playoff berth before Dallas head coach Bill Parcells parted ways with him.

FORT WORTH STAR-TELEGRAM/VIA AP

Quincy Carter was thrust into the role of Troy Aikman’s replacement and helped the Cowboys earn a playoff berth before Dallas head coach Bill Parcells parted ways with him.

Carter split starts the next season with undrafted free agent Chad Hutchinson, and then in 2003 started all 16 games and led the Cowboys to a playoff berth. But Carter, who struggled with drug problems during his career, was cut during training camp before the 2004 season.

The Cowboys then turned to veteran castoffs Vinny Testaverde and Drew Bledsoe in 2004 and 2005 until they finally found Aikman’s replacement in Tony Romo, six years after Aikman left.

Cowboys' record before and after Aikman
W-LPlayoff berthsNotable
Final five years with Aikman39-4131 playoff win
Five years after Aikman35-4510 playoff wins
QBs drafted in five years before Aikman’s departure
None

BRETT FAVRE

How he exited: After ending a short-lived retirement, was traded by Packers to Jets in 2007.

Age when he left: 38

Parting synposis: As bitter as a breakup can be. Favre didn’t want to leave, and may have felt pushed out by the Packers, who (smartly) had drafted Aaron Rodgers as insurance.

Aaron Rodgers was an understudy to Brett Favre for three seasons before replacing him.

Jonathan Daniel/Getty Images

Aaron Rodgers was an understudy to Brett Favre for three seasons before replacing him.

Favre had already talked about retiring (which would become a recurring theme) when the Packers drafted Rodgers with the 24th overall pick in 2005. He became Favre’s heir apparent, and a talented one. In Rodgers the Packers scored a QB many though was going to be the No. 1 overall pick in his draft (and in retrospect should have been). And while there was no immediate threat to Favre’s job, Rodgers represented a new era.

Favre did not like the idea that someone could force him out of a job.

There were early signs of the bad feelings to come when the Packers slumped to an 0-4 start in 2005 and whispers flew that they might yield the starting job to Rodgers.

“Something has to give at some point,” Favre said, “if I decide enough is enough or they do. I hope it’s on friendly terms, so to speak.”

But friendly terms never quite materialized. Favre decided to retire following a 13-3 season in 2007 (in which he lost the NFC title game in overtime at home) and the Packers committed to Rodgers as their starter.

But Favre changed his mind during the summer. He wanted his job back. The Packers didn’t want to give it to him. He dramatically showed up at training camp and in an awkward scene joined Rodgers on the practice field during a workout. Fans who loved Favre for a generation were split. The organization was not. Tired of the drama and uncertainty surrounding Favre, the Packers wanted the stability Rodgers would bring them.

So the Packers orchestrated a bizarre, middle-of-the-night trade to the Jets. Favre played out the 2008 season in New York, but found his way to Minnesota the next year to do what was so important to him — prove to the Packers they made a mistake discarding him.

Favre led the Vikings to a 12-4 mark in 2009 and, most importantly, notched two wins over the rival Packers, including a dramatic 38-26 victory at Lambeau Field in which he threw for four touchdowns. But those wins over the Packers would be the high mark of the Favre second act.

Favre achieved a goal when he beat Rodgers and the Packers in a Vikings uniform in 2009.

Tom Olmscheid/AP

Favre achieved a goal when he beat Rodgers and the Packers in a Vikings uniform in 2009.

He would throw a critical interception in overtime of the NFC title game that set up the Saints’ win over the Vikings. The next summer, the Vikings practically dragged Favre off his couch to play again, only to see him, at age 41, dogged by injuries that would force him to sit out a game for the first time in more than 18 years.

Meanwhile, Favre went 0 for 2 against the Packers in 2010 (the final loss a 31-3 rout) only to watch Rodgers march Green Bay to a Super Bowl title that winter. Favre would then retire — for good.

Aaron Rodgers led the Packers to a championsjup in Super Bowl XLV, something Favre had done in Green Bay 14 years earlier.

Jamie Squire/Getty Images

Aaron Rodgers led the Packers to a championship in Super Bowl XLV, something Favre had done in Green Bay 14 years earlier.

Packers' record before and after Favre
W-LPlayoff berthsNotable
Final five years with Favre45-3532 playoff wins
Five years after Favre53-2741 Super Bowl win
QBs drafted in five years before Favre’s departure
PlayerYearOverall pick
Aaron Rodgers200524
Ingle Martin2006148

PEYTON MANNING

How he exited: Colts cut him in 2012 after he sat out a year with a neck injury.

Age when he left: 35

Parting synopsis: The Colts’ approach was, plainly, “lucky” when Andrew Luck emerged to replace Manning.

The Colts had such an unstable backup plan that when Manning was lost for the 2011 season with a neck injury, they sank to the bottom of the NFL.

Suddenly, a team that had earned nine straight playoff berths was flirting with an 0-16 season. It wasn’t until Dec. 18, after 13 straight losses, that the Colts won a game.

The Colts were so unprepared to be without Manning that when it became clear he wouldn’t be ready to start the 2011 season, they signed Kerry Collins out of retirement. Collins lasted three games before yielding to Manning’s 2010 backup, Curtis Painter. But it was journeyman Dan Orlovsky who ultimately led the Colts to their only two wins of the season.

Curtis Painter went 0-8 when he became the Colts starter in the wake of Peyton Manning’s injury in 2011.

The Indianapolis Star/via AP

Curtis Painter went 0-8 when he became the Colts starter in the wake of Peyton Manning’s injury in 2011.

Manning’s injury ironically put the Colts in the enviable position of having the No. 1 overall pick in a draft that offered two potential franchise-caliber quarterbacks in Andrew Luck and Robert Griffin III.

And while Manning publicly insisted that the roster would have enough room for him and Luck, the reality was that the incoming quarterback needed a fresh start. So the Colts parted ways with Manning and drafted Luck. And just like Manning 14 years earlier, Luck stepped right in as the starter.

In another year, the Colts might not have been so lucky with the No. 1 pick. Few draft classes offer quarterbacks the caliber of Luck or Griffin. Had Luck or another elite prospect not been available, perhaps the Colts would have drafted at another position and Manning might have returned to Indianapolis.

It was little surprise when the Colts made Andrew Luck the first overall pick in 2012.

Al Bello/Getty Images

It was little surprise when the Colts made Andrew Luck the first overall pick in 2012.

But that still would have left the Colts with the problem (that currently faces the Broncos) of how to replace the now-38-year-old icon in the long term.

Colts' record before and after Manning
W-LPlayoff berthsNotable
Final five years with Manning*51-2951 title in 2 Super Bowl berths
First two years after Manning22-1021 playoff win
* does not include 2-14 2011 season in which Manning never played
QBs drafted in five years before Montana’s departure
PlayerYearOverall pick
Curtis Painter2009201

DREW BLEDSOE

How he exited: Traded by the Patriots to Buffalo in 2002.

Age when he left: 30

Parting synopsis: In an uncomfortable divorce, Bledsoe simply was beaten out by a better quarterback.

Drew Bledsoe did not expect Tom Brady to take his job and never give it back when he was injured in 2001.

Jim Davis/Globe Staff

Drew Bledsoe did not expect Tom Brady to take his job and never give it back when he was injured in 2001.

Bledsoe isn’t the same caliber quarterback as the others on this list, who are either Hall of Famers or likely to end up in Canton (Favre and Manning). But when he was dislodged by Brady in 2001, he was a franchise quarterback just eight months removed from signing a $100 million contract.

And Bledsoe’s story illustrates yet another way that an iconic quarterback can fall — he can simply be outplayed.

Brady originally became the starter when Bledsoe was injured on a hit by the Jets’ Mo Lewis as the Patriots fell to 0-2. Brady would stabilize the Patriots offense and preside over a 5-2 run before Bledsoe was pronounced fit to play in November.

Bledsoe did not return feeling entitled to the starting role, but he wanted — and said he was told he could have — a chance to compete for the job.

“I intend to make it very hard for Brady to stay on the field,” Bledsoe said.

Then, after the Patriots lost, 24-17, to the Rams at home in Bledsoe’s first game since being cleared (when Brady started and went 19 of 27 for 185 yards with one TD and two INTs), coach Bill Belichick declared Brady the starter for the remainder of the season.

Belichick said he changed his mind about the open competition and couldn’t devote time late in the season to evaluating quarterbacks. Bledsoe — who later acknowledged his relationship with Brady became “difficult” — was angry, though he pledged to support Brady and not to allow the issue to divide the team.

(Still, he couldn’t resist this zinger: “I look forward to the chance to compete for my job.”)

Bledsoe was true to his word. The loss to the Rams turned out to be the Patriots’ last as Brady led a run that resulted in the franchise’s first Super Bowl win. Bledsoe played a significant role, too, when he relieved an injured Brady in the AFC title game and threw a touchdown pass in a 24-17 win at Pittsburgh.

Without Bledsoe’s touchdown pass in relief of an injured Brady in the AFC title game, the Patriots may never have reached Super Bowl XXXVI.

Jim Davis/Globe Staff

Without Bledsoe’s touchdown pass in relief of an injured Brady in the AFC title game, the Patriots may never have reached Super Bowl XXXVI.

But Brady’s rise meant Bledsoe was done in New England. Even with a $100 million contract, he wasn’t reclaiming his job from a 25-year-old Super Bowl MVP who was only getting better.

Patriots' record before and after Bledsoe
W-LPlayoff berthsNotable
Final five years with Bledsoe43-39*31 Super Bowl berth
Five years after Bledsoe58-2043 Super Bowl wins
*  includes first two games of 2001 season started by Bledsoe
QBs drafted in five years before Bledsoe’s departure
PlayerYearOverall pick
Michael Bishop1999227
Tom Brady2000199

FORECAST: BRADY’S FUTURE IN NEW ENGLAND

So what can we take out of these lessons for how Brady’s exit from the Patriots might go?

Brady, who will be 37 on Aug. 3, has said he wants to play several more years and to remain in New England for the balance of his career. Patriots owner Robert Kraft said he wants the same.

Tom Brady said after Jimmy Garoppolo was drafted that he wants to remain the Patriots starter for a long time.

Michael Dwyer/AP

Tom Brady said after Jimmy Garoppolo was drafted that he wants to remain the Patriots starter for a long time.

And Brady knows — more than most, perhaps, after his experience with Bledsoe — how tenuous a starting quarterback’s hold on his job can be.

“There’s no entitlement in the NFL,” he told Sports Illustrated. “I don’t expect to be given anything. I just hope I’m the one most entitled to play that position for a long time here.”

But the realities of the NFL could disrupt the desire for Brady to play his entire career in a Patriots uniform. Montana went to the Chiefs. Manning now plays for the Broncos. There are no clearer examples of how icons can change uniforms in the NFL.

Belichick said after drafting Garoppolo that the Patriots felt compelled to act now at quarterback.

“We know what Tom’s age and contract situation is,” he said. “We needed to address that to some degree in the future, but I think you’re better off being early than late at that position.”

So, based on how Brady’s peers ended their tenures with their teams, here are some of the scenarios that could lead to him leaving the Patriots:

■ He could simply be outplayed by Garoppolo or someone else on the depth chart.

■ He could suffer an injury that hampers his effectiveness and then allows someone else on the depth chart to surpass him.

■ He could have a contract dispute through which the resulting bitterness between him and the Patriots leads the team to cut or trade him.

■ In a best-case scenario, he could win another Super Bowl with New England and then decide to leave the game as a champion.

■ He could remain with the Patriots as a top-echelon starter and decide at some point to retire even without winning another Super Bowl.

■ He could remain the starter while his skills deteriorate because no suitable option exists to replace him. That could lead to him retiring and the Patriots being without a succession plan.

■ He could decide to retire, then change his mind and demand his job back even after the Patriots have committed to his replacement. (OK, that one is really far-fetched. But at least there is a precedent.)

But Brady’s exit is only half of the equation. The Patriots must also focus on transitioning to a new quarterback. And recent history suggests they will struggle to compete at the same level they’ve been able to under Brady.

Consider that over the past 25 years, there have been eight Hall of Fame-caliber quarterbacks in the NFL who have had to move on from the team they became an icon with. Of those, only two teams — the 49ers after Montana and the Packers after Favre — transitioned to a quarterback who won a Super Bowl.

Four of the transitions (the Bills after Kelly, the Broncos after Elway, the Dolphins after Marino, and the Cowboys after Aikman) were very rocky. Another (the 49ers after Steve Young) was mediocre. It’s too early to judge the Colts after Manning, but with Luck taking the team to the playoffs in his first two seasons, the trend is certainly positive in Indianapolis.

The Patriots are trying to stay prepared for the uncertainty that will ultimately come when the Brady era ends.

They were smart to draft not only Garoppolo but also Ryan Mallett (in 2011). They have given the Patriots what Kraft has called “disaster insurance” — and a potential bridge to the future.

The second-round pick the Patriots invested in Garoppolo was the highest pick they used on a quarterback since Bledsoe in 1993.

Steven Senne/AP

The second-round pick the Patriots invested in Garoppolo was the highest pick they used on a quarterback since Bledsoe in 1993.

As most NFL coaches will tell you, it’s not easy to find quarterbacks who perform like Brady. And merely drafting Garoppolo doesn’t mean he’ll be a high achiever. (Look to the 1997 Bills and 1999-2002 Broncos as teams that have been let down by heir apparent quarterbacks.)

But here’s one key takeaway from the exits of the other iconic quarterbacks that the Patriots may have heeded: The two teams who moved on to quarterbacks who won Super Bowls (49ers and Packers) acquired their new signal caller long before the icon left. Of course, those two teams and quarterbacks also had the ugliest divorces (which could be an ominous sign for Patriots fans).

So adding Garoppolo shows the Patriots are 1. being pro-active so they’re ready for Brady’s departure, however it occurs; and 2. giving Garoppolo more of a chance to be successful by adding him to the roster before Brady leaves and allowing him not only to absorb the team’s offensive system but also to learn from Brady.

Related:

Christopher L. Gasper: Tom Brady still plenty good enough

Tom Brady: Wins are the only stat that matters

Robert Kraft wants Tom Brady to play whole career with Patriots

A lot of Tom Brady in Jimmy Garoppolo’s game

Jimmy Garoppolo awed by introduction to Patriots

Sean Leahy can be reached at sean.leahy@globe.com. Follow him on Twitter @leahysean.
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