One question has followed Aidan Miller since his days as a Florida prep star: will he stick at shortstop long term?
The 6-foot-1, 205-pound infielder shifted to third base as he physically matured in high school, but when the Phillies selected MLB’s No. 32 prospect in the first round of the 2023 Draft, they announced him as a shortstop.
While most scouts thought he’d have to switch back to the hot corner eventually, Miller has defied expectations by playing his entire pro career at short (aside from a handful of games at DH). And after a strong 2025 season between Double-A Reading and Triple-A Lehigh Valley, the 21-year-old — now the Phillies’ top hitting prospect — appears more likely than ever to stick at the 6.
“I think he matured well beyond his years this year,” Minor League infield coordinator Adam Everett said. “He’d never played in the cold when he got up there, and I think it got to him. He made a bunch of errors early, wasn’t swinging the bat well, but he really showed true resolve. The way that he overcame that, he just kept grinding, which was awesome, didn’t give up, didn’t quit, and he wound up having a heck of a year all things considered.”
There are plenty of Draft prospects who start at shortstop and move to another position over time, but it’s rare to see a high school third baseman move up the defensive spectrum. The club almost started from scratch in teaching Miller how to move like a shortstop and maximize his innate athleticism.
Miller has worked closely with Everett, a fellow shortstop who spent 11 seasons in the Majors and was also drafted in the first round (1998). They’ve focused on his pre-pitch and first step, backhand throws and countless ground-ball drills. Once a work in progress at the position, Miller has made steady progress to the point that there’s little doubt he can be a solid Major League shortstop.
It doesn’t hurt that Miller has long been able to make the kind of plays that turn your head despite being so new to the position.
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“The first time I saw him play, first time he played with us, a ball was smoked at him 105 [mph], something like that,” Everett said. “He took a step in, went back, caught it on a big hop and nice easy throw to first, and I went, ‘That’s just not something a lot of guys do. That’s a learned skill. He’s very instinctual.’ And that’s where the biggest thing was letting him be instinctual this year.”
Miller has plenty of arm for the left side of the infield, and he learned how to maximize that plus tool this year. And after working on his speed and quickness last offseason, he’s moving especially smoothly defensively now.
More than anything, Everett just thinks Miller needs more reps. The game may speed up on him as he spends more time at Triple-A, but Everett has coached many of baseball’s top shortstops in the Minors and sees Miller on a similar defensive path.
“I had the privilege of working with [Carlos] Correa when he first got signed and [Alex] Bregman, and even [Francisco] Lindor a little bit, but he reminds me a little bit of a combination of them,” Everett said. “His first step reminds me a lot of Correa, the way he moves is a little bit Corey Seager-ish, but there are similarities here and there of certain guys. But he’s kind of a mix of all, which is a really good thing.”
The Phillies are planning to keep Miller at shortstop as long as he can stay there. But the elephant in the room, of course, is that Philadelphia has an All-Star entrenched at short — Trea Turner signed an 11-year, $300 million contract seven months before the club drafted Miller 27th overall.
Turner, 32, is coming off the best defensive season of his career (11 outs above average) but had rated as a negative defender the previous five seasons. So Miller may well have to start his big league career at another position. If he does, it won’t be because he can’t play shortstop — more that it’s the easiest way to get his potential 30-homer bat into the lineup.
“There’s no question about his ability, and sometimes, to get to break in, you might need to break in in another position, and that’s OK,” Everett said. “He knows that, and he’s fine with that. He just wants to play in the big leagues, and that’s what all these guys are aspiring to do, but I don’t think it’s going to matter one way or another, honestly.”
