Detroit Tigers' Casey Mize has 'no concerns' about fatigue, explains rehab process

Detroit Tigers right-hander Casey Mize — rehabbing from elbow surgery and back surgery — planned to throw anywhere from 20-25 pitches in his second live batting practice session Wednesday at Comerica Park.

The 26-year-old ended up throwing about 17 pitches. Mize, the 2018 No. 1 overall pick, stopped Wednesday's session in the middle of a matchup with Akil Baddoo his because of arm fatigue.

"I felt like that was enough for the day," Mize said.

Manager A.J. Hinch, who watched Wednesday's session from behind home plate, wasn't concerned about Mize's inability to increase his pitch-count volume from his first live batting practice session, which featured 20 pitches.

LIVE BP NO. 1: Tigers' Casey Mize shows clean delivery, four-pitch mix to hitters for first time since surgeries

Mize shared insight into the lengthy rehab process in return from Tommy John surgery, offering an important reminder. (He underwent Tommy John surgery on June 15, 2022, then back surgery shortly after that.)

"No concerns," Mize said Thursday. "I love being up here throughout this process, but this is stuff that you all are seeing for the first time. This is not linear at all. In Lakeland, guys miss months with setbacks during this and nobody hears about it because they're away.

"There's just fatigue and feelings that come along with hitting a new step or doing something new that I'm going to have to work through. I've been doing that this entire process, and I'm going to do it now. This is nothing new and nothing concerning from our end from what this process looks like. It's just a hurdle to get through."

The Tigers decided to keep Mize around the big-league team for most of the 2023 season, both at home and on the road, to monitor his progress closely. The same happened when fellow pitchers Tarik Skubal and Matt Manning were on the injured list, as well as outfielder Riley Greene.

After Wednesday's live batting practice, Mize gathered near home with Hinch, pitching coach Chris Fetter, assistant pitching coach Robin Lund, video coordinator Austin Tripp and head athletic trainer Ryne Eubanks.

That type of interaction wouldn't have happened if Mize was stationed in Lakeland, Florida, at the spring training facility. Still, there's one drawback: In Lakeland, nobody is watching Mize; in Detroit, everybody is watching Mize.

"That's the slightly negative part of it," Mize said. "No hate or anything, but that's stuff that you guys are able to see that we're able to keep out of the spotlight down there. I still wouldn't trade it. I love being up here. I love it. But I'm just saying, you all are seeing the process of what this really looks like. It's not linear. It's not pretty. It's not amazing. It's ugly, and it's tough. There's stuff that comes up that you wish wouldn't, but you do what you do to get through it. That's what we're going to do."

The timing of Mize's second live batting practice session, just like the first live batting practice session, opened the door for an audience. There was a similar audience when Skubal threw his two live batting practices, without any setbacks, in return from left flexor tendon surgery.

WHAT HAPPENED: Why Tigers' Casey Mize ended second live batting practice earlier than expected

In Mize's case, everyone witnessed a 96 mph fastball and a revived splitter with nasty movement, just like everyone watched him call off his second live batting practice session after about 17 pitches.

"Had we not done it at 2 o'clock, it would have been sort of a non-event," Hinch said Thursday. "We're just going day-by-day so that he'll be honest with us when he doesn't feel great, and then all of a sudden, we can alter or lengthen his rest. I wasn't concerned about it. He wasn't all that concerned. We'll continue to go day-by-day."

Mize has started 39 games for the Tigers across parts of three MLB seasons. He looked like an ace in the making when he logged a 3.71 ERA and led the team with 30 starts and 150⅓ innings in the 2021 season.

In 2022, Mize posted a 5.40 ERA with two walks and four strikeouts across 10 innings in two starts with the Tigers before suffering the elbow injury. He hasn't pitched in a competitive game since May 12, 2022, a failed rehab start with Triple-A Toledo.

"We'll just seeing how the next few weeks play out for him," Hinch said, "without getting into any conclusions one way or the other."

Mize couldn't say whether or not he will begin a rehab assignment before the offseason. He almost certainly won't return to the Tigers in the 2023 season because there are 29 games remaining on the schedule.

"There's plenty of stuff I would love to do," Mize said, "but it might be disappointing if I can't, and it might be the best feeling in the world if I can. I'm hoping it's that. It's stuff I honestly cannot have an answer for. It's day-by-day, step-by-step, and then we move forward from there. I know that's not the answer anybody is looking for. That's not what I want to say either, but it's the truth."

Contact Evan Petzold at epetzold@freepress.com or follow him @EvanPetzold.

This article originally appeared on Detroit Free Press: Detroit Tigers' Casey Mize has 'no concerns' about latest arm fatigue