The apex predator for the U.S. worm population bides his time in the New York Yankees’ bullpen. He begins to stir in the later innings, and he enters in the eighth or ninth. Then his assault on the nation’s underground invertebrates begins. For All-Star relief pitcher Clay Holmes, the weapon of choice is a devastating sinker — and it has led to a record-chasing rate of balls pounded into the dirt, menacing whatever creatures have the misfortune of hiding below major-league infields.

Ground balls represent a slim plurality of balls put in play in Major League Baseball. Every year since 2002, as far back as FanGraphs has data, between 42.7 and 45.3 percent of batted balls have been on the ground. Some pitchers might generate rollers on 65 or 70 percent of the balls hitters put into play against them. The post-2002 record for highest ground-ball rate in a single season⁴⁰ belongs to Zack Britton, at 80 percent in 2016. Britton’s 2015 and ‘19 seasons are also second and third on the full-season leaderboard, respectively. But if Holmes keeps producing grounders at this rate, he’ll overtake Britton’s most worm-burningest seasons. Through games of July 12, Holmes’s ground-ball rate was 83 percent, the highest in at least 20 years. 

There is more to Holmes’s game than inducing grounders. In his 39 appearances covering 39⅓ innings, his strikeouts-per-nine-innings rate is 10 percent higher than league average, per FanGraphs. His walks per nine are 48 percent lower. He has swing-and-miss stuff and barely walks anyone. Put those traits together with what appears to be a historic ability to get hitters to drill the ball into the ground, and you get a sparkling first half that has seen Holmes post a 1.37 ERA (seventh-best among qualified relievers), take over the closer’s role in New York and earn his first All-Star nod. (Even if he did have a disastrous outing against the Cincinnati Reds earlier this week.)

But with enough grounders over the next two-and-a-half months, Holmes could become an all-time trivia answer. And whether he supplants Britton atop the grounder leaderboard or not, he has already become a model of athletes and their teams collaborating to get the most out of each other. The Yankees and Holmes realized he could throw one devastating pitch, and he started throwing it a lot. Bake in a few other improvements and a lot of help from his defense, and Holmes’s career has transformed overnight.

Holmes was always supposed to be a good big-league pitcher. The Pittsburgh Pirates drafted him in the ninth round in 2011 and paid him a $1.2 million signing bonus, a record for that round, to forgo a scholarship at Auburn and join the Pittsburgh farm system. He had a long, winding minor-league career that included Tommy John surgery in 2014 that wiped out his age-21 season. He worked his way through the minors after that, and following an impressive stretch in Triple-A in 2017 and ‘18, the Pirates brought him up at the end of that stretch. 

The majors were not kind to Holmes at first. He walked an unsustainable amount of hitters — 7.9 per nine innings in 2018, 6.5 in 2019 — and surrendered a 6.01 ERA in 76⅓ innings those two seasons. He struck out more than a batter per inning but could not overcome all the bases on balls, plus 11 hit batsmen and eight wild pitches. By 2019, the Pirates had abandoned the idea of Holmes being a starting pitcher. 

In keeping with the times, Holmes’s career hit a low point in 2020. The season was abbreviated for everyone but really abbreviated for Holmes, who was injured again and pitched just 1⅓ innings all year. The Pirates had a new front office, with Ben Cherington replacing Neal Huntington, the general manager who had made Holmes into a record-breaking bonus baby. Cherington kept Holmes around for just a bit longer, and after a better (but still not good) few months in 2021, the new Pittsburgh GM sent Holmes to the Yankees for infielders Diego Castillo and Hoy Park. 

The Yankees took a chance on Holmes, but they were not just wishcasting that he could fulfill some of his old promise. Within months of his July arrival, something dramatic happened with Holmes’ pitch usage, as chronicled by MLB’s Statcast data: The sinker, already his pitch of choice, really became his pitch of choice. He went from throwing it around two-thirds of the time in July and August to 76 percent of the time in September. Two other things happened to Holmes’s sinker: It got faster (averaging a career-best 96.8 miles per hour in September, about a full mile per hour better than it had been in each of the season’s earlier months), and it started to spin more than normal at 2,242 revolutions per minute, just a shade off a career high he’d set in May 2021. In 15 regular-season games in September and October, Holmes posted a 1.62 ERA with 23 strikeouts. The walks that had plagued him in Pittsburgh all but vanished in New York, where he walked just four batters in 28 post-trade innings. It was a turning point that the Yankees and Holmes have carried over into the current season. 

The sinker was always Holmes’s preferred pitch. He threw it about half the time during his parts of four seasons with the Pirates. But somehow, the Yankees helped Holmes throw it harder and with more movement. Naturally, they also had him throw it more. Holmes’s sinker usage is up to 82 percent of his pitches this season, which almost exactly matches his ground-ball rate. He has stopped throwing an ineffective curveball, and he maintains a slider as his only change-of-pace pitch. His sinker velocity is up to 96.9 miles per hour, and it moves nightmarishly, averaging 24 inches of vertical drop from his hand to home plate (4.1 inches more than average) while breaking 1.7 inches more than the horizontal average, too. By net run value, Holmes’s sinker is the 17th-most valuable pitch in baseball this year. (It was the third-most-valuable before Monday night’s fiasco against Cincinnati, perhaps a sign that hitters are figuring out his not-so-secret weapon.) When Holmes revs it up, his sinker looks like it is remote-controlled: 

Clay Holmes, Unfair Sinkers. pic.twitter.com/EwzBxSsP1f

— Rob Friedman (@PitchingNinja) June 18, 2022

All of it has made Holmes a hard man to touch — hence the high strikeout totals to go with all those grounders. When Holmes’s sinker is hit into play, its average launch angle is negative-13 degrees. This means he often puts the Yankees’ infield defense to work, and fortunately for Holmes, that is a premium product in its own right. New York leads baseball with 55 defensive runs saved, 14 more than the second-place Houston Astros. Catcher Jose Trevino leads with 14, and then comes a bunch of infielders: Josh Donaldson at third base (10), DJ LeMahieu at various positions (7), Gleyber Torres primarily at second base (5) and Isiah Kiner-Falefa at shortstop (4). The good gloving is a new development that has matched well with Holmes’s breakout season. Last season, the Yankees were second-to-last in DRS. They’ve made nearly a 180 in that category, thanks in large part to the addition of players like Kiner-Falefa, a Gold Glover at third base with the Texas Rangers who moved to shortstop in 2021.

Now, even when hitters get a hold of Holmes’s sinker, his teammates pick him up. A case in point: On April 26, the Orioles’ Jorge Mateo turned around a Holmes sinker at 108.7 miles per hour, the hardest anyone has hit the pitch in 2022. The play turned into a force-out when Kiner-Falefa dove for it and flipped it to LeMahieu at second base. Opponents’ batting average on balls in play against Holmes this season is .250; from 2018 to ‘21, it was an even .300. It helps to play in front of the league’s best defense.

The Yankees will always have a financial edge on the Pittsburghs of MLB. But the story of Holmes is one of them finding a strategic one. After all, New York did something that should not be possible: Doing a much better evaluation of a player who had spent years in another organization, even another league, than the team that employed that player. (Pirates manager Derek Shelton acknowledged in early July that Holmes’s success was cause for “self-reflection.”) Meanwhile, Holmes worked hard to improve his own pitching craft, adding more velocity and drop to his sinker. He overcame Tommy John surgery and all the other adversity that comes with a stop-and-go journey through the minors and some bad seasons with a bad Pirates team. Upon joining the Yankees, Holmes began throwing his best pitch with more electricity and frequency. 

This season, the Yankees beefed up their defense just as Holmes beefed up his sinker usage even more, creating a perfect symphony. The rest has been history — both for the opposing hitters pounding harmless grounders into the infield dirt and for any subterranean species caught in their path.

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