MONTGOMERY, Ala. — Theo Gillen, the Tampa Bay Rays’ No. 1 prospect and MLB’s No. 9 overall, broke out with his first Double-A homer as part of a multihit night, reaching base three times in the Montgomery Biscuits’ 5-1 victory over Knoxville at Riverwalk Stadium.
The 20-year-old out of Westlake High School in Texas roped a solo shot to right field off Knoxville starter Luis Martinez-Gomez, the Chicago Cubs’ No. 21 prospect, to even the score in the fourth inning. Gillen added a two-run double off left-hander Evan Taylor in the eighth to give Montgomery breathing room — his second extra-base hit of the night.
Gillen has slashed .213/.304/.328 since his promotion to the Biscuits on June 22, though the 15-game sample size is small. His bat is productive over a reasonable sample size, and he is making adjustments — hitting safely in six of his past seven games with nine RBIs in that span.
The breakout performance tracks with the trajectory Tampa Bay’s 2024 first-round pick established at lower levels. At High-A Bowling Green, Gillen clubbed 12 homers in 57 games and posted a 1.038 OPS. Before that, he turned in a .820 OPS across 73 games for Single-A Charleston in 2025. The Rays have moved him aggressively through their system, pushing him to Double-A after just 138 professional games.
Gillen carries a pair of 60-grade tools atop the Rays’ prospect rankings. He already showcased his talent on a national stage during the All-Star Futures Game at Citizens Bank Park, collecting an RBI single off southpaw Kash Mayfield, the San Diego Padres’ No. 4 prospect.
Montgomery continues its series against Knoxville at Riverwalk Stadium, where Gillen will look to build on the hottest stretch of his young Double-A career.