After signing Trea Turner to a $300 million deal over 11 years, the Philadelphia Phillies were primed for a championship run in 2023. Following a 3-1 National League Division Series win over the top-seeded Atlanta Braves, the Phillies went into the NLCS as the heavy favorites. Going up against the 6-seeded Arizona Diamondbacks, who barely made it into the postseason, the Phillies quickly went up 2-0. The Phillies would then win one out of three in Arizona to take a 3-2 series lead back home, where they had not lost all playoffs. Unfortunately, they would lose two straight and be knocked out on their home field in a 4-2 Game 7 defeat. In the 2023 draft, they selected high school shortstop Aidan Miller.
Despite already having signed Turner for the foreseeable future, the Phillies could not deny the talent Miller possessed. While many scouts and fans alike assumed he would learn third base, he has yet to play there in his pro career. It could stand to reason that the Phillies, however, want his bat to settle in before changing his position. Seeing as he is still only 21 years old, it is still likely he makes the swap to third base. This would track as he has above-average arm strength, and while he has average defense at short, it would become above average at the hot corner.
Now in his third professional season, Miller carries a career .773 OPS across four levels. Despite only playing 20 games his first year, Aidan Miller was still able to see Low-A pitching. In his first full season, he played 102 games at three different levels. Starting at Low-A, he posted a .275 average and a .884 OPS in 39 games. He then moved up to High-A, where he slashed .258/.353/.444 through 58 games. Additionally, Miller posted 30 walks and 12 steals to go along with 24 extra-base hits and 32 RBI. This success saw him make it to Double-A at the end of the 2024 season for five games, where he struggled. In those games, Miller only had four hits while walking once and striking out four times.
Now in 2025, he has played all 73 games at Double-A, where he has slashed .225/.345/.365 thus far. It has been an up-and-down season for Miller, as while he has 35 steals and 46 walks, he has struck out 83 times. Additionally, he has 20 XBH, 10 being doubles, two being triples, and the other eight being home runs. Despite this, Miller is only 21 years old and has plenty of time to adjust and rebound before the Phillies call him up.
Aidan Miller sizzles his 8th Double-A @ReadingFightins homer of the season
MLB’s No. 21 prospect (@Phillies) has posted a .452 OBP over his past 10 games: pic.twitter.com/CLKPUj3uNG
— MLB Pipeline (@MLBPipeline) July 13, 2025
As long as he stays a Phillie through the trade deadline, it would seem Miller eventually becomes their primary third baseman alongside Trea Turner on the infield. However, seeing as Philly is contending, Miller could end up going to another team. If this does happen, it is a possibility that he stays at the shortstop position, unless the team already has a defined future there. Overall, whether at third or short, Aidan Miller should see big league action by the end of the 2026 season. Once there, he can showcase the raw power and speed that got him drafted straight out of high school.
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