There may be more to Colin Holderman's recent Pirates struggles than his injury

Heading into the 2024 season, Pittsburgh Pirates reliever Colin Holderman looked to build off his breakout 2023 campaign. He finished the year with a 3.86 ERA, but a 3.29 FIP (that hinted at some positive regression), paired with a slightly elevated 1.34 WHIP. He kicked off his 2024 campaign with a bang. His first 37.2 IP yielded a 1.67 ERA, 3.01 FIP, and 1.22 WHIP.

During that time, he struck out 28.7% of opponents with a HR/9 rate of 0.43. Opponents couldn’t seem to make hard contact vs Holderman. He induced an average exit velocity of just 86.2 MPH. He had an unimpressive 11.3% walk rate and 10.6% barrel rate, but those were about his only blemishes to that point of the year.

But now Holderman has allowed at least one earned run in five straight outings. He has taken the L in four of those appearances, allowing eight earned runs, walking more batters (three) than he’s struck out (one), and giving up a whopping four home runs. Holderman allowed just two home runs from July 23, 2023 through July 24, 2024. But what happened? How did Holderman go from a quality setup man to one of the roughest stretches of his entire career?

What happened to Colin Holderman, and can the Pirates solve it?

So far, the stuff hasn’t been the problem. His overall pitch quality has looked better, in reality. Stuff+, a measurement that shows how good or bad a pitcher's pitches are based on speed, spin, release point, and movement (and on a scale akin to wRC+, OPS+, ERA+, etc.), put Holderman at 113 from the start of the year through July 27, the day prior to his collapse. Since then, he’s seen that go up to 129. That currently leads Pirates pitchers in this particular stretch.

But the location of his pitches is the issue. Location+ is described as a “count- and pitch type-adjusted judge of a pitcher’s ability to put pitches in the right place,” per FanGraphs. For example, a slider thrown out of the zone while ahead in the count is graded a lot differently than a slider outside the zone when a pitcher is behind in the count. Location+ put Holderman at 96 up until this slump, but is down to 87 throughout this poor stretch of games.

That might not seem like a huge drop, but keep in mind, no pitcher this season with at least 30 innings pitched is below 90 in Location+. The biggest drop has been in the quality of location of Holderman’s sweeper. His sinker and cutter had a Location+ rating of 94 and 90 heading into July 28. That has barely changed, with his sinker at 95 and his cutter at 89. But his sweeper’s Location+ mark has gone from 101 to just 80.

Holderman has had trouble throwing his sweeper in the zone when he is ahead of batters. 6.5% of his sweepers landed somewhere in the zone from the start of the year through July 27. Now, only 0.3% have hit the zone during this stretch when he is ahead in the count.

A look at his heat map of his sweeper location shows why he’s taken such a hit in Location+. Most of Holderman’s sweepers prior to his struggles landed down and away to righty batters/down and in to lefty batters. Sweepers in this part of the zone aren’t hit very well across the league. They have led to a .186 batting average, .590 OPS, .266 wOBA, 36.6% whiff rate, and 84.5 MPH exit velocity.

But now, Holderman is throwing his sweeper more middle away to righties/middle-in to lefties and up and away to righties/up and in to lefties. He has also left a handful of sweepers hanging. Sweepers in this part of the zone have resulted in a .271 batting average, .884 OPS, .372 wOBA, a whiff rate of just 16.7%, and 89.6 MPH exit velocity.

Not being able to locate this pitch effectively is huge, given it’s the best pitch in Holderman’s arsenal. Since 2023, opponents have just a .189/.238/.259 line and a .222 wOBA against Holderman’s sweeper with a 37.8% whiff rate. When they do make contact with Holderman’s sweeper, they’ve only managed an 85.5 MPH exit velocity and 6.7% barrel rate. There have been 61 pitchers that have used their sweeper against 100+ batters since the start of ‘23. Holderman has the 10th-lowest opponent wOBA and 12th-highest whiff rate with his sweeper over the last two years.

So how can Holderman solve these issues? The Pirates have decided that, for the time being, they're going to blame his struggles on injury, placing the right-hander on the IL prior to Thursday's game with a right wrist sprain. Holderman landed on the IL twice in 2023. The first time was on June 15, and the second time was on September 22. Holderman looked bad in both cases before being placed on the IL. In his four appearances prior to hitting the IL in mid-June of last year, he allowed six earned runs on two home runs and ten hits. Holderman’s final three outings of 2023 saw him give up seven earned runs on seven hits and three walks. 

If Holderman's struggles persist when "healthy," the second thing that could help solve some of the righty's issues is to change how he throws his sweeper. Something is definitely wrong with the way he's executing the pitch. He's leaving it in spots that are very hittable. He needs to figure out a way to regain the control of his sweeper without compromising its overall integrity.

Holderman’s inability to locate his sweeper effectively has been a huge detriment to the bullpen. The Pirates’ pen has been strained all year, and heading into July 27, Holderman had the best ERA and most innings pitched among Pirates relievers. Whether his downturn can be blamed on an injury or something else remains to be seen. Something needs to be done quickly, however, because this is a serious issue and has cost the Pirates many close games already.