With help from TB12, Aidan Miller is healthy, grateful for adversity, and primed to impact the Phillies in 2027

Three years ago, four friends celebrated the end of their first season as professional baseball players by getting together for a golf trip to Port Charlotte, Fla.

“We’re actually doing that this winter, too,” Aidan Miller said. “It’ll be fun to reunite with those guys.”

Imagine the new stories they could tell.

Colt Emerson, a 21-year-old shortstop, got called up by the Mariners in May and homered for his first major league hit. Bryce Eldridge, a 21-year-old Giants first baseman, banged 17 homers, including a walk-off grand slam in June. Kevin McGonigle, a 22-year-old shortstop from Delaware County, signed a $150 million contract with the Tigers in April, came home to play in the All-Star Game in July, and is the presumptive American League Rookie of the Year after a 7.1-WAR season.

» READ MORE: Dave Dombrowski didn’t have an ‘elite’ season. And turning it around in 2027 won’t be easy.

And Miller? The 22-year-old Phillies top prospect had a decidedly different 2026. Back pain sidelined him in spring training, and a complex diagnosis and monthslong recovery caused him to miss nearly the entire season, clouding his promising career.

But he returned to the field last month, won an Eastern League championship with double-A Reading, and is off to a blazing — and most importantly, healthy — start in the Arizona Fall League.

Miller’s tale might still have a happy ending.

For the Phillies, it’s practically an imperative.

“I’m not gonna put it on his back,” president of baseball operations Dave Dombrowski said Thursday, pun most definitely unintended, “but we think Aidan Miller is a really, really good player. You see all the young players that jumped into playing this year and the years they had. Aidan Miller, when healthy, he’s as good as any of them.”

Indeed, a bumper crop of 23-and-under infielders burst onto the scene this season. The rookie class included McGonigle, JJ Wetherholt (Cardinals), Konnor Griffin (Pirates), Travis Bazzana (Guardians), A.J. Ewing (Mets), Eldridge, Sal Stewart (Reds), Cooper Pratt (Brewers), Emerson, and George Lombard Jr. (Yankees), some of whom have the look of franchise cornerstones.

The Phillies planned for Miller to make a similar impact, maybe not on opening day but certainly later in the season. They even assigned him a spring-training locker between Bryce Harper and J.T. Realmuto, and down the row from Trea Turner and Kyle Schwarber, to make him comfortable around the team’s stars.

“I think he would’ve played for us in ’26,” Dombrowski said, “if, unfortunately, his back wasn’t in that situation.”

Before a game Thursday in Arizona, Miller appeared as a guest on The Inquirer’s Phillies Extra podcast and said his back feels “as close to 100% as I can get.” He insisted his condition is “not even a thought anymore” and outlined the training program that is designed to keep it that way.

Miller traced the origin of the back problem to the final week of last season and credited the Tampa branch of Tom Brady’s chain of “TB12″ training and recovery centers for helping to identify and treat it.

And although he conceded that the misery of not being able to play was compounded by his friends’ successes, Miller also believes that the ordeal gave him a different appreciation for the game.

“I was super happy for them, but obviously, yeah, a little frustrated like, ‘Hey, that also could be me up there,’” Miller said. “But it’s honestly changed my whole outlook on baseball. I think in the past I was so worried about all my stats and how’s our team doing — we’ve lost three in a row, things like that. It’s just like, man, it’s a blessing to be playing baseball every single day.

» READ MORE: The Phillies will keep Trea Turner at shortstop for now: ‘He knows he has to be better’

“The fact that I get to do this as a job is incredible.”

Dombrowski’s job is to extend the Phillies’ competitive window with a core of thirtysomething stars and $239.25 million in luxury tax commitments for 2027. He expressed gratitude for ownership’s largesse, but also interjected reality, especially amid uncertainty over the financial rules whenever baseball emerges from a labor battle over a new collective bargaining agreement.

“We have a lot of high-salary guys at this point, so I think you have to figure out which way you go,” Dombrowski said. “I don’t think it necessarily means signing all high-salary guys, but I do think we have the flexibility. … The reality is that, ‘Hey, it’s up to me. I’ve created the situation, right?’"

How much better would that situation be if Miller is the Phillies’ version of McGonigle?

With a powerful right-handed swing, the athleticism to play shortstop, and instincts on the bases, Miller is cut from central casting as a five-tool prospect.

But one month into the season, he was casting lines in Tampa Bay.

“I got really big into fishing,” Miller said. “Every time a guy would come down to rehab, I hated it for him, but it was nice because I had a new fishing buddy. [Triple-A infielder] Keaton Anthony was down for a bit, and we’d go out and fish for like eight hours every day, just to get our mind off the grind of rehab.”

Miller’s back began to flare up near the end of the 2025 season. He described a “tight and tense” sensation when he swung a bat. And the more he swung, the worse it got. With two games left in the triple-A season, he met with the athletic trainers.

» READ MORE: The big offseason questions facing the Phillies: Core’s future, fixing the bullpen, and who’s managing?

“I was like, ‘Hey, I want to get an MRI, kind of see what’s going on,’” Miller said. “And they shut me down the rest of the year.”

Instead of playing in the Arizona Fall League, Miller went for daily treatment at the Phillies’ facility in Clearwater, Fla., a half-hour drive from where he grew up. Mostly, though, his back responded to rest.

Miller didn’t hit much until spring training. And in his first at-bat against a pitcher, he twisted out of the way of a wayward pitch and felt his back tighten up again.

“It felt like I was back at square one,” he said. “And it wasn’t getting any better.”

Over the next two months, Miller got multiple opinions from back specialists in between cortisone shots and other treatment. In June, the Phillies disclosed a two-pronged diagnosis: discogenic pain, and facet inflammation in the lumbar spine. Miller underwent a radiofrequency ablation, a minimally invasive procedure that uses needles and heat from radio waves to block a nerve from sending pain signals to the brain.

“When I first heard it, I was like, ‘I’m not doing that,’” Miller said. “And then I read a little bit more into it, and it’s very non-invasive.”

It also didn’t work.

“I went in, I did it, and the doctor says like, ‘Three or four days, let the shot kick in, let your body kind of reset,’” Miller said. “And it honestly didn’t bring me much relief.”

A few weeks later, Miller was referred to Brady’s TB12 wellness and fitness center in downtown Tampa. After a three-day trial that involved massage and soft-tissue therapy, he was told that the tightness was less about his back than weakness in the muscles around it, including the glutes and psoas.

Eureka!

“I remember my first session with them, it probably lasted like two hours, it was gone. My pain was gone,” Miller said. “And I was like, OK, there’s something to this. The pain came back probably 24 hours later, but the fact that we could get it to go away that fast was the first time I’ve had that sensation in that whole process.

“So, I started going back to them every single day.”

Phillies medical coordinator Justin Ahrens went with him and “basically mastered the soft-tissue aspect of what they do,” Miller said. It became critical treatment for an issue that he now refers to as “chronic tightness” rather than a back condition.

“You see people with chronic back pain, they can’t do anything,” Miller said. “Usually like sitting down hurts for a long period of time, like when they wake up. I didn’t have any of that. ... It was more of just being so tight that everything was just kind of relying on my back, which was giving me the pain. The pain wasn’t really stemming from the back.

“And the more I’ve loosened that up — I have a good routine now where I’m laying on massage balls, moving through it, getting in the gym, still working on my core, still working on all that stuff — the better I feel.”

Miller calls it “bulletproofing the back.”

“That’s just something I’m going to have to do for the rest of my career,” he said, “which is good because it makes me feel great in all aspects.”

Miller returned to the field on Sept. 5 — 354 days after his last game. He doubled in his first at-bat for low-A Clearwater and played five innings at shortstop.

Three days later, he joined double-A Reading.

The Phillies outlined a plan for Miller to spend one week there and the last week of the season in triple A. But when Reading qualified for the playoffs, Miller wanted to stay put.

“I called the front office,” he said. “I was like, ‘I want to stay here. I want to play for a championship. I think this is really important for me; it’s important for the team.’”

» READ MORE: The most imaginative changes the Phillies can make begin with moving Trea Turner off shortstop

Reading swept Hartford and Erie in a pair of best-of-three series to win the club’s first outright Eastern League championship since 1995. Miller had two hits, including an RBI double, in the clinching game.

“It was a great end to a long year,” he said. “I think winning is the best development, knowing what it’s like to be in a pressure situation. It’s like, ‘Hey, I’ve got to get this run in at the plate.’ ... Just knowing how to win, doing the little things, backing up a base, saving a run, stuff like that.”

Miller, who models his game after former Phillies free-agent target Bo Bichette, is playing third base in the Fall League, a potential precursor to replacing free agent Alec Bohm. But Dombrowski also met with Turner this week and issued what amounted to an ultimatum: Improve your defense, or get moved off shortstop.

In that case, Dombrowski mentioned Miller as an alternative there.

First, there’s another few weeks in the desert, where Miller was 7-for-14 with a double, a triple, and 10 walks through five games. Then, there’s that golfing trip with his buddies, former teammates on the U.S. national under-18 team.

In 2023, the Phillies drafted Miller 10 spots ahead of McGonigle, even though the eventual Tigers star grew up in their backyard. Miller said he talks to McGonigle “all the time” on a group text message.

“He’s always been one of the best hitters I’ve been around, man,” Miller said. “He’s so mature for his age. It didn’t surprise me at all to see what he did this year.”

Imagine what it would mean for the Phillies to get that from Miller next year.

Watch the latest episode

After missing almost the entire season with a back condition, Aidan Miller is off to a hot start in the Arizona Fall League. The 22-year-old infield prospect joined Phillies Extra, The Inquirer’s baseball podcast, to discuss his recovery and why he believes the injury is behind him. Watch here.

You can also subscribe to the podcast version of Phillies Extra on Spotify or Apple Podcasts.

Previous episodes: Scott Franzke | Larry Andersen | Matt Klentak | Jeff Francoeur | Luke Murton | Mike Hazen | Tony Gwynn Jr. | Kevin Stocker | Bobby Dickerson | John Middleton