The Arizona Diamondbacks' hopes of a sooner-than-later Corbin Burnes return took a hit on Wednesday afternoon, with the news that the ace righty had suffered an injury setback during his Tommy John surgery rehab — a Teres Major strain, unrelated to his elbow injury. The new injury, Burnes told reporters at Chase Field Thursday, "shocked everyone." The right-hander said he had felt a minor tweak in his shoulder, almost "like a cramp back there." To be safe, he went for imaging; to the surprise all, that imaging revealed brutal news.But Burnes, who was already on an extremely aggressive timeline in his Tommy John rehab, said he's fully intent on pitching again this season, and hopes to be back before September, if possible. When will Corbin Burnes pitch again for Diamondbacks?Arizona Diamondbacks pitcher Corbin Burnes is interviewed by the media at Chase Field in Phoenix on Sept. 29, 2025. | Rob Schumacher/The Republic / USA TODAY NETWORK via Imagn ImagesWhen asked point blank if he expected to pitch again, Burnes said, "Absolutely," without an ounce of hesitation, though he added the specific timeline is still "up in the air." He's currently shut down from throwing entirely. "It's going to depend on when I get back to throwing," he said. "Depending on how long I have off throwing, obviously depends on the time it takes to build back up. If it was up to me, I would still be playing catch, but I've got to listen to the training staff as much as I can. I think there's definitely a goal to be back for at least September, if not more.""I'm going to push the envelope. It's what I do. I pushed the envelope to get back two months earlier in T.J, so whatever the timeline is, I'll make sure it's on the short end of that. But just have to do what I can to get healthy and provide as much of an impact as I can."Did aggressive rehab timeline cause Burnes' setback?Arizona Diamondbacks manager Torey Lovullo and pitcher Corbin Burnes (right) during spring training workouts on Feb. 10, 2026, at Salt River Fields in Scottsdale. | Rob Schumacher/The Republic / USA TODAY NETWORK via Imagn ImagesThe natural question that arises in a situation like this is whether or not Burnes' already-aggressive Tommy John surgery timeline — which was a targeted mid-July return — contributed to the new injury. Burnes does not believe that to be the case."I don't think me pushing a Tommy John rehab had anything to do with this," he said. "I think it's more just the time we had off from competitive action. ... Elbow was great. Elbow's still great. We're completely over that now."He also said he does not think it had to do with any difference or tweak to his delivery. "That's what's kind difficult with this type of injury, is you don't really know where it comes from, whether you had a little change in the arm action or just whatever it may be. We can't wrap our head around it. We don't know. "There was nothing as far as tinkering with arm slot or anything. Everything literally was the same for the two months of bullpens leading up to game action last year."It's just weird that it happened," Burnes added. "Only thing you can really say is just the increase in intensity, the tissue just wasn't ready for it after a long layoff. That's really all it is."Corbin Burnes on his frustration levelArizona Diamondbacks' Corbin Burnes (39) pitches against the Washington Nationals at Chase Field in Phoenix on June 1, 2025. | Joe Rondone/The Republic / USA TODAY NETWORK via Imagn ImagesIt was certainly a blow for the Diamondbacks, who got just 11 starts of 2.66 ERA baseball from Burnes in 2025. It was also frustrating for Burnes himself, who was set to begin his rehab assignment in the Arizona Complex League on Friday. That won't happen, now. "The last couple of days have been tough," he said. "It's tough to have put in work for 11 months and you're a little over a month away from being back. It's tough."Burnes said he's taken solace in the fact that he's able to be home with his family, and being a father to his young son and twin girls. "I was kind of working my way out of it, starting to worm out of it a little bit, but now we're right back in the thick of it.Will Corbin Burnes opt out of his contract?Arizona Diamondbacks pitcher Corbin Burnes is interviewed by the media at Chase Field in Phoenix on Sept. 29, 2025. | Rob Schumacher/The Republic / USA TODAY NETWORK via Imagn ImagesBurnes, who is on a six-year, $210 million deal, has an opt-out in his contract after this season. He did not have an answer when asked about that possibility. "We haven't thought about that yet," he said. "That's an offseason thing to deal with."Add us as a preferred source on GoogleFollow