One after another, the Texas Rangers made the long, sad march back to the dugout.

Red Sox ace Chris Sale once again proved overpowering, mixing fastballs approaching 100 miles per hour with virtually unhittable sliders. Of the 21 outs Sale recorded in seven innings Wednesday, 12 came by strikeouts.

What followed proved just as unrelenting, and in the end, Red Sox pitchers struck out 18 batters. Yet this rare display was barely distinguishable from the back-to-back games with 13 strikeouts in Kansas City over the weekend or the 11- and 10-strikeout games that immediately preceded them.

Was the idea of an 18-strikeout performance in the Red Sox’ 4-2 win on Wednesday shocking?


“No,” shrugged Sale. “Not given the guys we have on this staff.”

Strikeouts in Major League Baseball now come in a blur. The Fenway Park siren that punctuates each strikeout echoes in the park so often that it seems like a constant soundtrack to the game.

That stands in contrast to what seems like a bygone time when the strikeout represented such a novelty that each one required an act of documentation and celebration. Roger Clemens and Pedro Martinez seemed like giants among boys, their ability to neutralize opposing bats almost unfathomable.

Now, strikeouts are so commonplace that in the eyes of some fans and observers, they border on an epidemic that threatens the popularity of the game. Yet those who know all that goes into producing them marvel at what they’re seeing.

“It’s amazing how fast [the strikeouts] add up and at times you don’t even notice it,” Red Sox pitching coach Dana LeVangie said. “It happens at times effortlessly. It’s just insane how quick it goes.”

Major league pitchers this season have struck out 22.3 percent of batters — approximating the career rate of Clemens (23.1 percent). The Astros’ staff has struck out 29.1 percent of hitters — a mark that surpasses three of Martinez’s historic seven seasons in Boston.


In 2005, strikeouts occurred in 16.4 percent of plate appearances. That number has crept up in 13 consecutive seasons — the longest uninterrupted upward trend in major league history — to 22.3 percent this year. Overall, strikeouts are up 36 percent in that time.


The explosion of stuff

The steady climb in strikeouts has had a companion. Average major league pitch velocity has likewise experienced a significant rise.

In 2001, according to Fangraphs, the average major league fastball was 89.0 miles per hour. That number has climbed this year to 92.8 m.p.h. What once qualified as an average fastball is now a disqualifying trait for big league pitchers.

Ten years ago, roughly one out of every 14 pitches in a big league game was thrown at 95 m.p.h. or harder. Now, that number is one out of every nine pitches. Particularly in the late innings, high-octane stuff is the norm.

“Every team’s bullpen, there’s no 92-93 and nibbling. They come with 96,” said Red Sox shortstop Xander Bogaerts. “These guys in the bullpen now, I don’t know who you want to face out of the bullpen now. It’s a joke how good they are.”

Red Sox manager Alex Cora has talked about the changing role of bullpens — how the value of driving up the pitch count of an opposing starter in order to knock him out early has diminished in an era when middle relievers emerge with high-90s lightning and nasty breaking balls. Starters are now replaced not out of necessity but instead as soon as managers feel their bullpen gives them an increased likelihood of an out — and usually, a strikeout.


“Stuff-wise, those guys on the mound, they’re a lot better,” said Cora. “There’s no more 87, 88 in the middle of the game. You go from the starter to the first reliever, he’s throwing 98. It’s tough.”

Fastballs by the numbers
Year Average velocity (m.p.h.) Usage (pct.)
2018 92.7 55.2
2017 92.8 55.6
2016 92.3 56.7
2015 92.1 57.7
2014 91.8 57.7
2013 91.7 57.8
2012 91.6 57.6
2011 91.5 57.8
2010 91.2 58.7
2009 91.2 59.7
2008 90.7 60.7
2007 90.3 60.6
2006 90.5 61.1
2005 90.1 61.9
2004 90.1 62.6
2003 89.4 63.8
2002 89.0 64.4
SOURCE: FanGraphs

Better fastballs . . . and fewer of them?

At the same time that fastballs have gotten better, pitchers have become less wedded to them. While fastball velocity has been rising steadily, the frequency with which that pitch is thrown is declining, falling (according to Fangraphs) from 64.4 percent in 2002 to 55.2 percent this year. Whereas hitters once could have sat on fastballs and been right roughly two-thirds of the time, there’s now a lot more guesswork involved.

And just to make the task of hitters even harder, secondary pitches have become sharper and more deceptive. The explosion of pitching analytics — the ability to define precisely the spin rate, spin axis, velocity, and movement of pitches; a more precise understanding of the value of sequencing and mixing pitches — has allowed players and coaching staffs to work together to emphasize wipeout pitches while leaving lesser offerings at the curb.

“If you give engineers a wind tunnel, they’re going to figure out a way to make the gas mileage on your car 10 percent more efficient. If you give intellectual baseball people who understand the body and the physics of the ball and the game the tools to actually study it, they’re going to find ways to make pitches 10 percent more efficient. That means 10 percent more movement, that means 10 percent more swing and miss. It just adds up all over the place,” said Red Sox vice president of pitching analysis Brian Bannister. “Essentially, baseball has become a game full of data scientists. We’re finding ways to get better at what we do, and to provide the players with better information and better recommendations on everything they do on a daily basis.”


Joe Kelly (left) has struck out 41 batters this season, and Craig Kimbrel has whiffed 58.
Joe Kelly (left) has struck out 41 batters this season, and Craig Kimbrel has whiffed 58.Jim Davis/Globe Staff/File

Pitchers are gaining real estate

The data-driven study of pitching has included a growing awareness of the dimensions of the strike zone as called — a phenomenon that changes over time.

Analysts such as Jon Roegele of Fangraphs and The Hardball Times documented the steady expansion of the strike zone from 2009-15, with most of the expansion occurring below the knees.

The actual size of the strike zone has mostly stabilized in recent years — though in the last few years more strikes are being called at the top of the zone, an area where hitters are particularly vulnerable to swings and misses.

Home plate umpire Marvin Hudson punched out Rangers hitter Joey Gallo during Wednesday’s game at Fenway Park.
Home plate umpire Marvin Hudson punched out Rangers hitter Joey Gallo during Wednesday’s game at Fenway Park.Jim Davis/Globe Staff

A changed outlook

According to Fangraphs, big leaguers have a .683 batting average and 1.583 OPS when hitting line drives. On fly balls, they have a .229 batting average and .908 OPS. On ground balls, those numbers are a .235 batting average and .491 OPS. Of course, strikeouts produce a .000 batting average.


Logic suggests that the most effective tool of run prevention is the strikeout. Pitchers recognize this. They are no longer waiting until they reach two-strike counts before they look to put away an opponent. Virtually every pitch is meant to elicit a whiff, a fundamental change in how the game is played.

“The biggest change in the game is the mind-set of, ‘Get a hitter out in three pitches or less.’ Efficiency was the most prized thing in baseball,” said Bannister. “Now, the whole art of pitching is the science of the swing and miss . . . When we can control all the variables with a ball not being put into play, as opposed to a ball being put into play and all the chaos that causes, it’s worth our time and effort. That’s how pitching has evolved.”

With pitchers placing ever greater emphasis on getting swings and misses, there are two potential responses for hitters. One would be to change approaches to emphasize more contact. Yet given how much stuff has improved and how good pitching plans of attack have become, such adjustments would only go so far in combating the strikeout surge.

Meanwhile, because of what pitchers are doing, the value of a contact-oriented approach that produces a wealth of singles is less than it once was. In the era of swing-and-miss stuff, it’s hard for teams to string together three hits to scratch out a run.

And so, many major leaguers take a different view. Rather than looking to minimize the amount of swing-and-miss, they look to maximize the amount of damage done when making contact.

“With two strikes, you used to think, ‘He’ll go the other way.’ Defense would kind of shift. But now, two strikes, you’re staying in your position, because he’s probably going to hit it hard or strike out. That’s definitely an adjustment,” said Red Sox right fielder Mookie Betts. “Even with two strikes, you’re still looking to do damage. If they make a mistake, I still want to hit my double or a homer versus a single.”

With that outlook comes a situational acceptance of strikeouts. Cora and other members of the Red Sox point out that there remain situations where a strikeout is more than just an out — with a runner on third and no outs or especially one out, for instance, a lack of contact represents a squandered opportunity to score — but there’s also a willingness to embrace a risk/reward model.

“If you put a competitive at-bat and if you’re swinging at strikes, everybody is OK with some strikeouts,” said Red Sox hitting coach Tim Hyers. “To be a successful team, you’ve got to impact the baseball and slug it harder than the average team, in my opinion. You’ve got to take some chances.”

The faces of failure: From left to right, top to bottom: Giancarlo Stanton, Andrew Benintendi, Chase Headley, Tucker Barnhart, Daniel Robertson, and Kenta Maeda.
The faces of failure: From left to right, top to bottom: Giancarlo Stanton, Andrew Benintendi, Chase Headley, Tucker Barnhart, Daniel Robertson, and Kenta Maeda. Associated Press and Getty Images

Beyond the K’s

For all the discussion of the prevalence of strikeouts, it’s worth noting that the ability to limit whiffs has been a hallmark of some standout offenses.

“The two teams that I’ve been around the last two years as a coach and as a manager, they put the ball in play, so I do feel that’s very important,” said Cora, who was the bench coach for last year’s Astros.

The Red Sox this year are hitting for power yet have the lowest strikeout rate (19.6 percent) in the majors. The ability to combine those traits has helped them to lead the majors in runs.

Last year, the Astros led baseball in runs and slugging percentage, while posting the lowest strikeout rate (17.3 percent), and they won the World Series. In 2016, the Cubs trimmed their strikeout rate from 24.5 percent (the highest in the majors in 2015) to a middle-of-the-pack 21.1 percent, and they won the World Series. The 2015 Royals won the World Series with a contact-heavy approach that resulted in the lowest strikeout rate in the majors.

So, at a time when strikeouts are rising, there is clearly value to contact — particularly when that contact yields extra-base hits. Not all teams and not all players believe in two-strike approaches, but the ability to excel when one strike from a punchout has been a common denominator of recent champions. The Astros, Cubs, and Royals all finished in the top three in the majors in OPS with two strikes.

Moving forward

Changing approaches, however, can only do so much to curtail strikeouts. If baseball is interested in seeing more frequent contact, then rule changes are a likely consideration — as was the case when the mound was lowered in 1969 and the designated hitter introduced in 1973 in reaction to a period from the 1950s to late ’60s of steady strikeout rate increases and offensive declines.

From 2006-14, a significant downward trend in offense occurred in tandem with the rise in strikeouts. From 2015-17, the explosion of home runs had helped to reverse that trend even with the ongoing rise in strikeouts, but this year, with home runs down and strikeouts up, offense is once again declining, a concern to MLB industry members who worry about the inaction in the game.

Any number of possibilities — strike zone changes, mound height changes, alterations to the composition of the baseball — could alter the dynamic. It’s worth noting that this 13-year trend of increasing strikeout rates is an aberration in baseball history. And so, there’s awareness on the part of the industry that baseball might alter some of the governing rules.

“We’re prepared for any scenario. We’ve talked about every kind of rule change, every kind of rule that we could do, depending on what’s ultimately mandated to us, and to react and put the best product on the field accordingly,” said Bannister. “We’re going to push the limits on everything because that’s how you win baseball games. If you’re not trying to, you’re not trying to win.”

Alex Speier can be reached at alex.speier@globe.com. Follow him on twitter at @alexspeier.