How Brewers Will Try to Make Lance McCullers Jr. Serviceable Again

Lance McCullers Jr. probably won't become one of the Brewers’ best starters in the second half. The Astros wanted to dump most of his salary for a reason. McCullers is four years removed from performing like a viable big-league starter, and he’s currently working his way back from a shoulder injury. The Brewers have taken fliers on several injured pitchers in recent years, such as Trevor Rosenthal, Nestor Cortes, and Shelby Miller, and the returns have been next to nothing.

There’s certainly room for the veteran to make an impact, though. Back-end starting pitching is a need for the Brewers, who recently lost Brandon Woodruff until at least September and just placed Kyle Harrison on the injured list with forearm tightness. The club seems to believe that the current version of McCullers, while diminished from his prime, can start games down the stretch with competitive enough results.

In the late 2010s, when spinning the ball became all the rage in pitch design and usage, McCullers was among the poster children. From his debut in 2015 through 2022, he posted a 3.48 ERA, 3.35 FIP, and 3.73 SIERA while throwing high-spin breaking pitches 45.8% of the time, more than any other pitch group. His signature pitch was his knuckle curveball, which he famously threw for 24 straight pitches to close out Game 7 of the 2017 ALCS.

Injuries began to strike near the end of that run. McCullers underwent Tommy John surgery after the 2018 season but remained productive after rehabbing. He then suffered a flexor strain during the 2021 postseason, and while he returned to make eight starts in 2022, he ultimately required surgery that sidelined him for the next two seasons.

He hasn’t been the same since returning. In 94 ⅔ innings over the last two seasons, a sample interrupted by four more trips to the injured list, McCullers has pitched to a 6.65 ERA, 5.48 FIP, and 4.73 SIERA. Never a great control pitcher because of his big breaking ball, he's seen his walk rate balloon to 13.7% during that stretch.

Hitters are seeing different stuff from this version of McCullers. His sinker used to sit around 94 MPH, but this year it’s averaged 91.3. He’s no longer a spin-first pitcher, either. After dabbling with a cutter for a few seasons, McCullers has made it one of his primary pitches for the first time this year. He’s now throwing fastballs 54% of the time, tied with his rookie campaign for the highest usage of his career.

That change suggests McCullers is feeling things out without much success. That also applies to his mechanics. Overall, he seems to be searching for what kind of pitcher he should be at this stage of his career, and he hasn’t yet found a clear answer.

After that original flexor injury, McCullers did not make his 2022 debut until August. He returned with a lower arm slot, a change that stuck through his two-year absence after surgery. This year, his slot was back to where it was before the injury, but it has dropped again during his rehab outings in Triple-A this month, which isn’t reflected on the chart below.

McCullers has typically worked from the first-base side of the rubber, where his crossfire delivery can be most on-line to home plate, and the arm-side run of his sinker plays up best. But in one outing last July, he relocated to the middle of the rubber. After that, he switched back.

With an in-season acquisition, the Brewers don’t have time to make wholesale changes, but helping McCullers establish an identity on the mound must be the starting point. Can he be a spin-heavy guy again, or is the fastball-centric approach the new way forward? Should he attack the strike zone aggressively or work the corners? How does his body move best after myriad injuries?

On the arsenal front, there’s still plenty to like about his curveball, which has induced a 48.1% whiff rate and a .291 xwOBA. However, McCullers has lost his feel for locating it competitively, throwing nearly a quarter of his curveballs in what Statcast defines as the waste zone. Those are pitches so far outside the strike zone that they rarely force a hitter to swing, which makes a nasty pitch far less useful.

The Brewers could try to make the curveball the centerpiece of McCullers’s arsenal again, but given their usual approach and where McCullers is right now, they’re more likely to emphasize his fastballs. Pitching coaches Chris Hook and Jim Henderson want starters to get early swings that miss barrels, which usually means sequencing sinkers, cutters, and four-seamers within the strike zone.

McCullers now has that three-fastball mix, and his sinker and cutter are the only two pitches in his arsenal without a negative run value this season. Throwing the latter more often might be the key to reducing his walks while playing the east-west game to both sides of the plate. Pitch models grade his cutter as the best among his fastballs, and it has posted a +1 run value and 20% whiff rate this year.

However, while McCullers has used the pitch as his leading fastball against left-handed batters, he’s thrown it more sparingly against right-handers. For comparison, Brandon Sproat, who has very similar pitch shapes from nearly the same arm slot, has used his cutter at nearly equal rates against both sides.

McCullers clearly is not what he once was, but he might also have more potential for a decent second act than those numbers suggest. His 4.55 xERA, calculated by Statcast based on what usually happens on the kind of contact a pitcher allows, is passable. According to Baseball Prospectus, his 4.43 DRA is slightly better than the league average. McCullers has still generated whiffs on 27.3% of swings and posted a 44.8% ground ball rate, both of which are above average.

The plan to be serviceable again will be somewhat tailored to McCullers as an individual, but expect the Brewers to turn to some familiar tricks. He’ll probably stay on the first-base side of the rubber. There might be small changes to his starting position and tempo to help get his arm on time and his torso more direct to the plate at foot strike. Attacking the zone with sinkers and cutters will probably be the playbook in most outings, with the expectation that an athletic defense will help him out on balls in play.

It’s best to keep expectations measured. McCullers is a struggling rental pitcher, and he may not even be the main get of this deal for the Brewers. Left-hander Colton Gordon comes with five years of team control and might be more impactful when all is said and done. That said, few clubs are better than Milwaukee at turning struggling starters into serviceable arms for a brief stretch, including starters with underwhelming fastballs like McCullers. Perhaps he’ll follow in the footsteps of Colin Rea, Bryse Wilson, and Aaron Civale, among others.