LAKELAND, Fla. -- Tigers right-hander Casey Mize, currently rehabbing from Tommy John surgery he underwent last June, revealed Wednesday that he also underwent surgery to address a longstanding issue with his back.

The surgery, which took place after the Tommy John surgery, is not expected to impact Mize’s rehab timetable. The former No. 1 Draft pick has been cleared to start a throwing progression this week, according to the team. Still, it adds another dimension to the issues he was battling last year, when he was limited to two starts for Detroit before he was shut down in June.

Mize did not specify the type of back surgery. But he said it addressed an issue that had been bothering him for far longer than the elbow.

“I’d say years,” Mize said. “It’s just something that’s gradually gotten worse over time. We had a unique opportunity with me having the Tommy John surgery to go ahead and tackle this, because there was available time for it to be done. So we decided if we’re going to focus on getting better, get everything better. That way when I come back, I can be the best player I can be, and be completely healthy.”

Asked if the back issue might have contributed to the elbow injury, Mize said, “It was something I had to tackle daily, and it probably led to some mechanical things that I didn’t love or some compensation. Any injury can have that effect. I would be a liar if I said it didn’t affect my elbow. Everything affects everything.”

The Tigers have not put a timetable on Mize’s return. Mize said his rehab timetable is “fluid.”

“The Tommy John rehab is not a definitive timeline,” Mize said. “We’ve seen it especially with our team, with different guys. Some guys get back in 'X' amount of months; some guys, it takes longer. It’s tough to make decisions on Feb. 15 about what July 1 is going to look like, about what Oct. 1 is going to look like.

“Obviously, we have a set schedule and a program that we’d like to follow, but this thing is fluid. There’s going to be changes throughout.”

Any return this season would arguably be a bonus for a Tigers rotation that has prepared to go through the season without him. After Detroit used 17 starting pitchers last year, new president of baseball operations Scott Harris signed left-hander Matthew Boyd and right-hander Michael Lorenzen to one-year contracts to fill out a rotation that is expected to include lefty Eduardo Rodriguez and righties Spencer Turnbull and Matt Manning. Turnbull is fully cleared to compete this Spring Training after undergoing Tommy John surgery in July 2021.

Like Mize, lefty Tarik Skubal is rehabbing from surgery, in his case a procedure to repair the flexor tendon in his left forearm. The Tigers haven’t put a timetable on his return, but he’s likely to pitch at some point this season.