Prospect Aidan Miller fits in at Triple-A with ‘very mature approach to the game’
ALLENTOWN, Pa. — Aidan Miller crept up to the infield grass as he manned shortstop in the ninth inning of his first game in Triple-A. With the visiting IronPigs clinging to a one-run lead, Scranton/Wilkes-Barre had put runners on second and third with one out. Miller got into position to mow down the potential tying run at the plate.
Then, the ball found him. Miller fielded a chopper off the bat of Bryan De La Cruz, planted his feet and calmly fired a strike to catcher Josh Breaux, who tagged out a sliding Ismael Munguia. The timely, run-saving play by the top prospect was not the most eye-catching highlight. But to veteran Christian Arroyo, it “looked like it was in slow-mo” from across the diamond at first base; the 21-year-old Miller had demonstrated an advanced level of control and feel for the game.
“I just think the kid is very mature for his age,” Arroyo, a former regular second baseman with the Boston Red Sox, said. “I think he’s got this internal clock about him that you see a lot of the really, really, really good players, that they just kind of naturally have.”
Miller, a first-round draft pick in 2023, passed his first test on his highest stage yet in that International League debut on Sept. 9. He completed that defensive play at a time when some other young players might have rushed it. He drew three walks against Kenta Maeda, a pitcher with nine years of big-league experience, as Lehigh Valley held on for a 5-4 victory. And Miller’s success has only continued in his short stint in Triple-A.
“He’s got a very mature approach to the game,” Arroyo said. “He understands himself, takes good care of himself and he plays. He’s a gamer. He wants to win. But he’s just a great kid, and he’s going to be a very, very good player.”
Starting the year at Double-A Reading after finishing the 2024 season there, Miller struggled in the first half, just as he did when he first got to High-A the year prior. It took an adjustment period, but Miller has bounced back in the second half. He’s slashing .284/.429/.483 in his last 63 games between Reading and Lehigh Valley and has a 1.033 OPS in eight games with the IronPigs. Overall, Miller is hitting .264/.392/.433 with 14 home runs and a staggering 59 stolen bases in 116 total games.
“It’s been good,” Miller said Thursday at Lehigh Valley’s Coca-Cola Park. “Things clicking on all cylinders. My all-around game, just getting more comfortable out there, being myself, letting the game play itself out and being more aggressive.”
One of the best prospects in the Phillies system, the organization promoted Miller to Lehigh Valley earlier this month to allow him to finish out the year at the top level of the minor leagues. He adapted to Double-A and dominated this summer, so the franchise gave him another challenge. Miller said that the IronPigs, a team with both up-and-comers and guys who have been around the majors like Arroyo, have welcomed him “with open arms.” He’s fit right in with his performance, as well.
“I’ve been impressed,” Lehigh Valley manager Anthony Contreras said. “I’ve been impressed, mainly by his poise and wherewithal within the game here in Triple-A. He doesn’t seem overmatched. I think he’s getting exposed to some better pitching, a little bit better defense and hitting as far as levels go. But for the most part, he’s holding his own.”
Contreras said he thinks this opportunity could help “propel” Miller ahead of next season. There’s a good chance that the infielder is back in Triple-A to start 2026 — and maybe even a slight possibility of him competing for a job on the Phillies roster out of spring training. These couple weeks of experience with the IronPigs certainly won’t hurt to have under his belt.
For now, Miller has three more games left in this minor-league season. He’s then scheduled to play in the Arizona Fall League to finish out what’s been a positive 2025 campaign.
“It’s been a great year,” Miller said. “I wouldn’t want it any other way. Going from not playing too well to playing better, it’s just the ups and downs of baseball. Not everything’s going to go your way. That’s why the game is so hard, and that’s why I love it.”