Rays Counting on Outfielder Debuting in Top 100 Prospect Rankings

The Tampa Bay Rays would benefit greatly from this outfield prospect reaching his ceiling.

Mar 21, 2018; Port Charlotte, FL, USA; A view of Oakley sunglasses on the New Era Spring Training hat in the game of the Boston Red Sox against the Tampa Bay Rays at Charlotte Sports Park. | Aaron Doster-Imagn Images

The Tampa Bay Rays are never going to be a team that spends a lot of money in free agency, putting them behind the eight-ball when it comes to competing with their rivals in the American League East.

The Baltimore Orioles, Boston Red Sox, New York Yankees and Toronto Blue Jays have all been major spenders at one point or another. That puts a lot of pressure on the Rays’ front office to find talent in the draft and for the staff to develop them.

Heading into 2026, Tampa Bay has a solid but not spectacular farm system, which is a surprise given how much talent the team has acquired in recent months via the 2025 MLB Draft and in trades, such as outfielder Jacob Melton.

Time will be needed for some of their top players to develop, but one that they have high hopes for is outfielder Theo Gillen. A first-round pick in the 2024 MLB Draft, he was a shortstop in high school who has been converted into an outfielder by the Rays.

Theo Gillen shooting up MLB prospect rankings

Dec 8, 2025; Orlando, FL, USA; Tampa Bay Rays manager Kevin Cash speaks with the media during the 2025 MLB Winter Meetings at Signia by Hilton Hotel. | Mike Watters-Imagn Images

He has looked good out there thus far, which certainly plays a part in his debuting in Keith Law’s Top 100 Prospects list over at The Athletic (subscription required). Gillen has come in at No. 67 and is the second-highest-ranked Tampa Bay player on the list.

The only player ahead of him is shortstop Carson Williams, who is ranked No. 54.

Right now, the best attribute that Gillen has is his discipline at the plate. He rarely swings at pitches outside of the zone, which is a major contributor to his impressive .433 on-base percentage in his first full season as a professional with Single-A Charleston.

However, his patience is a double-edged sword. Not swinging at pitches outside of the zone is great, but he hasn’t shown much aggressiveness going after pitches in the zone yet as a professional, either.

Gillen had a 60% swing rate at pitches in the zone in 2025. That would have been near the bottom of the MLB, coming in at the 15th lowest mark.

He did have a strong .278/.435/.407 slash line heading into the All-Star break, but wore down as the season moved along. A .224/.406/.306 slash line was produced in a small sample size after the break, before a calf injury sent him to the injured list.

That was the third time he was sidelined by injury last year, which could certainly have contributed to his lack of power. Only 20 years old, his first year was solid for sure, and there is plenty of untapped potential for the organization to work with.