SURPRISE, Ariz. -- If you ask Jack Leiter, you shouldn’t bet against Kumar Rocker.
The former college teammates at Vanderbilt are once again set to be in the same rotation with the Rangers, but Rocker’s 2025 left a lot to be desired.
The 2022 first-rounder broke camp with the big league club last season, but he dealt with both mental and mechanical struggles, posting a 5.74 ERA across 64 1/3 innings. Rocker was optioned to Triple-A Round Rock on Aug. 1, and shortly thereafter, he was shut down to refine his mechanics and work on his delivery.
Now, he’s back in camp, competing for the Rangers’ fifth starter spot in 2026, but it won’t just be handed to him.
“I don't know what his mindset is in terms of something to prove or what it might be,” Leiter said. “But I think he's got a chip on his shoulder. It's going to be fun to watch, because -- yeah -- I've never bet against that guy.”
Looking back, Rocker was maybe not fully ready for the mental and physical grind of the big leagues. But after a string of injuries in camp last season -- mainly to Jon Gray and Cody Bradford -- Rocker found himself in the rotation on Opening Day after just 64 2/3 professional innings between 2023-24.
His 64 1/3 innings in 2025 were by far the most he’s pitched in a season since his junior year at Vanderbilt in ’21 (122 IP).
“It was a big jump,” Rocker said. “But I like being thrown into the fire. Sometimes it works out, sometimes it doesn't, but you learn from it quick.”
Looking back to last year, Rocker points to a number of things that led to his lack of success at the big league level -- a routine that was out of whack and an ineffective changeup chief among them. All of those things he worked on during his developmental period at the end of the season.
“I just had to learn what I needed to improve on at the next level,” Rocker said. “I think I had the time to do that and just nail it down and have something to take into the offseason. … No major changes, but I'd say just tweaks in general so that I can be more efficient throughout the year.”
Rangers manager Skip Schumaker acknowledged that Texas also wasn’t in a place last season to let Rocker go through some of his struggles at the big league level. Teams who are not competing for the postseason are allowed to let things ride out. The Rangers were competing every day until the end.
“He is a very talented, special pitcher,” Schumaker said. “He has stuff that a lot of guys don't have on the mound. We want him to be hungry to make this team and do whatever he can to be one of the five guys, however it shakes out. I think he's doing everything he can to get there. There's some growing pains with a lot of young pitchers. It's just the reality. It takes time. But I think he's ready to take the next step.”
President of baseball operations Chris Young always says that pitching development isn’t linear. Rocker’s timeline is clearly indicative of that. Young pitchers go through growing pains. Rocker was and is no different to this day. And the Rangers still believe he has the talent and work ethic to reach his full potential.
Now he just has to do it.
And if you ask Rocker, he likes the competition. He likes having to earn it.
“100 percent,” he said. “I think that's part of it. I think that's why we play the game. I don't know how it plays out, but I know the work that was put in. Hopefully that translates.”
“I want him to go get it,” Schumacher added. “I think the main thing for him is to just go get it. Win the job. It’s there for him. Just go and take it.”