After 20 years, the NFL no longer revolves around Tom Brady and Bill Belichick

Tom Brady and Bill Belichick in 2018, the quarterback's penultimate season in New England.Jonathan Wiggs/Globe Staff

Gods do not answer letters. However, even gods must answer to expiration dates.

Tom Brady and Bill Belichick are finding that out. Neither man looked like his legendary self this season. Both displayed signs of decline. Both are sidelined instead of on the sidelines for the NFL’s divisional playoff round this weekend, a rarity.

This will be just the fifth time since the 2001 season that Brady and Belichick are spectators on Divisional Weekend. It happened in 2002 (Brady’s first full season as a starter), 2008 (Brady tore his ACL), 2009, and 2019 (Brady’s final miserable slog in Fort Foxborough).

Everyone’s day in the sun, no matter how long, eventually ends. Light shines on someone else. The NFL has moved past the duopoly of Brady and Belichick. After 20 years, the league no longer revolves around them. It was inevitable, but that doesn’t make it any less jarring.

Belichick has always said that in the NFL some are closer to the beginning of their careers and some are closer to the end. Both he and Brady are nearing the finish line of canonized careers that will land them in Canton, Ohio. Belichick will be 71 in April. Brady, who would be 46 if he suited up for a 24th season, has already stiff-armed Father Time better than anyone before him.

But after having the wind at their back for 20 years, much of it spent together dominating the league, the pair of legends looked more mortal and more vulnerable than ever, losing to teams and losing in fashions previously unthinkable.

You never bet against these men. If anyone can rebound, it’s Brady and Belichick. But they’re facing more questions and more doubt about their ability to write the endings to their storybook careers on their terms.

The Patriots stumbled to an 8-9 mark and missed the playoffs for the second time in three seasons post-Brady. Their offense was inept to a degree not seen since Belichick’s first season, 2000, when Brady was a fourth-stringer eating nachos in the stands. The Patriots struggled in the red zone, ranking last in touchdown percentage (42.2 percent).

The decision to install loyalists Matt Patricia and Joe Judge as architects of his offense was an unmitigated disaster for Belichick as players openly carped and quarterback Mac Jones regressed. The Fightin’ Belichicks feasted on bad teams and mediocre QBs to reach their finale needing a win over Josh Allen and the Bills to make the playoffs. Instead, they suffered a fourth straight double-digit loss to their former foils.

Now, Belichick has been chastened by his bosses, Robert and Jonathan Kraft, his carte blanche replaced by a letter to season ticket-holders promising “critical evaluations” of Belichick’s fiefdom and an unprecedented press release detailing plans for his coaching staff.

Brady’s season wasn’t much better. He dealt with personal and professional strife after coming out of a short-lived “retirement” for a 23d season. He finished with a losing record for the first time as a starter (8-9), although the Buccaneers, having already secured a playoff berth, pulled him before halftime of their regular-season finale loss to the Falcons.

Tom Brady walked off at Raymond James Stadium in Tampa after losing to the Cowboys. Will he be back?Mike Ehrmann/Getty

While he set an NFL record for completions (490), this was far from vintage Touchdown Tom. He suffered a three-game losing streak for the first time since 2002. He lost five of six for the first time. It wasn’t just that he lost. It was how and to whom.

Brady’s Bucs actually registered fewer offensive points than the Patriots. New England finished 22d with 310 offensive points and Tampa Bay was 24th (306). Tampa had no running game (last in the league) and no reliable third pass-catching option.

The Buccaneers lost to Pittsburgh and rookie Kenny Pickett, to Carolina and former XFL QB P.J. Walker, and to Cleveland and Brady’s former understudy Jacoby Brissett. In Brady’s homecoming to face his boyhood team, the 49ers, with his parents in attendance, the Buccaneers got pasted, 35-7, by a team led by rookie seventh-round pick Brock Purdy.

If it weren’t for a pair of classic Brady fourth-quarter comebacks against the Saints and Cardinals, Tampa Bay would’ve missed the playoffs too.

That actually might have been preferable to getting blasted in the wild-card round, 31-14, by the Cowboys. Brady looked his age, throwing an ugly red zone interception in which he pirouetted away from pressure. That continued a season-long self-preservation trend, with Brady looking like a guy who after two-plus decades of taking hits wasn’t willing to take any more.

Belichick and Brady will be forever linked for their six-ring dynasty. Now they’re linked because they’re simultaneously at a career crossroads.

Since parting, Brady has five playoff wins, three playoff appearances, and one Super Bowl ring. Belichick has two losing seasons, one playoff appearance, and zero playoff wins.

But Belichick is a sure bet to be back next season. Brady isn’t. Belichick is 19 wins from passing Don Shula for the most in NFL history.

He won’t walk. The Krafts will have to pull the plug. That was previously unthinkable, but another losing season could at least lead to contemplation.

Brady must decide whether he wants to play at age 46 and where. Brady sounded like a man saying au revoir to Tampa Monday night. Just how much is he willing to put into it and sacrifice on the family side? His children with ex-wife Gisele Bündchen reside in South Florida. His eldest child, Jack, lives in New York.

Reuniting with Josh McDaniels in Las Vegas looks good on paper, but it’s not convenient from a family perspective. The same goes for playing for his hometown 49ers, if they want him. Does Brady really want to continue as a New York Jet or a Carolina Panther? There’s no obvious fit for him right now.

Then there is the idea of a reunion with the Patriots. That seems like a long shot.

The future is uncertain for both Brady and Belichick. Will they power through the tape or face-plant?

The latter seems unthinkable. But for so long so did the notion that Brady and Belichick weren’t perpetual Super Bowl contenders, or that they would be idle by the Divisional Round, a place they reached together every year from 2010-18.

Now they’re just part of the pro football pack, not the leaders of it.