Phillies Top 30 Prospects No. 16: Carson DeMartini a Sneaky Base Thief

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

While he’s naturally right-handed, Carson DeMartini bats from a left-handed stance, making him an immediate rarity on the left side of the infield. The Phillies selected the 5-foot-11, 197 pound 23-year-old in the fourth round of the 2024 MLB Entry Draft.

He got off to a hot start for Single-A Clearwater before that season wrapped up, slashing .315/.385/.478 with nine extra base hits and eight steals in 24 games. Despite possessing below average speed, DeMartini has excellent feel for the basepaths, helping him swipe 45 bases between High-A Jersey Shore and Double-A Reading during the 2025 campaign.

DeMartini continued to burn through opposing pitchers with the BlueClaws, earning his Double-A call-up in early June. He struggled in Reading, slashing .202/.291/.288 over 66 games — hitting just two homers in that span after clubbing eight in 53 High-A games — but should make his big league debut sometime in 2027.

DeMartini walks in roughly one-tenth of his plate appearances but also strikes out 27 percent of the time, well above the league average. He struggles against left-handed pitching and off-speed pitches, which could limit his ceiling, but DeMartini’s ability to get on base and wreak havoc with his legs raises his floor, especially if he can continue to fool opposing catchers as his scouting file grows.

While the Phillies drafted DeMartini as a shortstop, he spent most of his time at third base last season. That said, his power stands out less at the corner spots. DeMartini also played at second during spring training this year, perhaps an indication of the club’s long-term plan for him.