The Philadelphia Phillies entered spring training with expectations that some of their top prospects would make their major league debuts this season. Andrew Painter and Justin Crawford are both on track to make the Phillies' Opening Day roster. Aidan Miller, who wasn't going to make their roster at the beginning of the regular season, but still had an opportunity to impress, has instead suffered a setback this spring due to a back injury.
Miller, the Phillies' top-ranked prospect, according to MLB Pipeline, demonstrated his potential during the final two months of the regular season last year. His success led to his promotion from the Reading Fightin' Phils in Double-A to the Lehigh Valley IronPigs in Triple-A in September 2025. He dealt with back discomfort while with Lehigh Valley, which ended his season and prevented him from participating in the Arizona Fall League, via The Philadelphia Inquirer's Scott Lauber (subscription required).
Phillies manager Rob Thomson isn't concerned about Aidan Miller's back issue
Phillies manager Rob Thomson gave an update on Miller on March 7, relayed in a video captured by Grace Del Pizzo. Despite the recurring nature of Miller's injury and a trip to a specialist, he remains unconcerned.
"[Aidan] went to Philly to see our doctor yesterday, just to see another doctor [about his back issue]. to close a loop on all the medical people," Thomson detailed.
The skipper then responded to a question about what the outlook and timeline is for Miller following the prospect's visit with the team doctor in Philadelphia:
"We don't have a timeline. I mean, he hasn't swung a bat in two weeks, so we just wanna get him healthy where there's no pain, [and] get him back to playing."
Thomson said his level of concern with Miller's injury is "none" and that "we'll take care of it."
Aidan Miller went to Philadelphia yesterday to see the Phillies’ doctor about his back issue.
— OnPattison (@OnPattison) March 7, 2026
He hasn’t swung a bat in two weeks; however, Rob Thomson’s level of concern is “none.”
(via @GraceDelPizzo) pic.twitter.com/7FF6KxM3wT
In a conversation with NBC Sports Philadelphia's Cole Weintraub, Miller said he expects his back ailment to sort itself out:
"It's not going to be a long-term thing," Miller assured. "Hopefully, I can get past it right now and not worry about it again. Nobody is more frustrated than me that I'm not out there. I'm just trying to be involved as much as I can, stay around the guys, ask a bunch of questions."
The Phillies planned to give Miller reps at third base originally in spring training. He's unlikely to see time playing shortstop, his natural position, with Philadelphia, due to Trea Turner's presence. With third baseman Alec Bohm a free agent next offseason and not likely to re-sign with the franchise, the Phillies will need a replacement at the position. Miller's a candidate to make his major league debut during the second half of the regular season if he continues to excel in the minors this year.
Miller may not be ready to play with the IronPigs at the beginning of the regular season due to his back injury. The Phillies will be cautious with their top prospect. However, optimism remains that the 21-year-old infielder will progress in the minors this year and potentially make his MLB debut during the 2026 season.