Earlier this summer, Theo Gillen vaulted into the conversation as one of the top 10 prospects in the game. And to cement that hard-earned reputation, he boosted his resume Wednesday with entrance into a rather exclusive club.
MLB’s No. 9 prospect launched his 15th home run of the season in Double-A Montgomery’s 8-6 loss to Birmingham at DABOS Park. Gillen became the third player in the Minors this season with at least 15 home runs and 30 stolen bases. He joined Eric Hartman (ATL No. 2/MLB No. 76) and Anthony Huezo (HOU No. 17) in that company.
The Rays’ top prospect lofted his third Double-A homer in the eighth inning, going back-to-back with Brayden Taylor, against right-hander Phil Fox (White Sox).
Double-A is said to be the hardest level for prospects to adjust to in the Minors, and Gillen is still working on tapping into his power regularly after showing plenty of pop at High-A Bowling Green with 12 home runs in 57 games with a 1.038 OPS prior to his promotion.
COMPLETE RAYS PROSPECT COVERAGE
Tampa Bay’s 2024 first-rounder (18th overall) got rolling in his first full season in 2025 with an .820 OPS in 73 games for Single-A Charleston. After his hot start this year at High-A, Gillen struggled in the early going with Montgomery, then turned a corner in July. During an active eight-game hitting streak, the 20-year-old is hitting .333 (11-for-33) with nine RBIs. He’s logged 18 total bases since returning from the All-Star break.
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Even his break wasn't that quiet as Gillen singled in a run during the American League's 6-1 victory at the All-Star Futures Game. And the latest achievement was just another example of the bright future Tampa Bay is predicting for its top prospect in the not-so-distant future.