Phillies Top 30 Prospects No. 1: Aidan Miller’s Improving Bat

This is the last in a series of stories breaking down the Philadelphia Phillies’ Top 30 prospects heading into 2026.

Another highly-rated prep pick, the Phillies selected Aidan Miller at the tail end of the 2023 draft: while he’d entered the field ranked as the No. 13 prospect, a hand injury during his senior year and the signing bonus north of $3.1 million he commanded helped him fall into Philadelphia’s lap. Miller stands 6-foot-1 and weighs 205 pounds, an athletic shortstop with a powerful bat who will make his big league debut before the 2026 season ends.

His bat improved across each of his first three professional seasons even as he climbed through the ranks of the Phillies’ system. There weren’t any growing pains during his late season stint with Triple-A Lehigh Valley last year, where Miller posted a 1.033 OPS in eight September games. A trendy pick to make the Phillies’ roster out of spring training, a lower back ailment hampered his swing and kept him from practicing.

Miller has plus power at shortstop, hitting 27 doubles and 14 home runs in 116 games last season. He also possesses savvy on the basepaths, stealing 59 bases in that span despite average speed. He’s swung and missed more as he continues to add power but also does an excellent job of getting on base, drawing 82 walks to balance out his 123 strikeouts in 2025.

Back issues are a concern to monitor for any prospect, but Miller’s strong arm and defensive ability means he has a future on the left side of the infield: if he can stick at shortstop, his offensive production adds another boost to the lineup.