Marlins Top Prospect Determined to Refine Mechanics and Learn Fast

The Miami Marlins top prospect is ready to prove his worth this spring training

Jacksonville Jumbo Shrimp pitcher Thomas White throws a pitch | Corey Perrine/Florida Times-Union / USA TODAY NETWORK via Imagn Images

Miami Marlins prospect left-handed pitcher Thomas White is coming into spring training highly focused and prepared to make a big impression. 

The young prospect is putting in relentless hours in the gym and on the field, working side by side with coaches and learning as much as possible. 

The 21-year-old is one of the top prospects in the Marlins system after being selected in the first round of the 2023 MLB Draft. 

There’s a strong possibility we'll see him debut sometime this season. In the meantime, he’s taking the time to get to know a lot of his teammates and learn from them. 

“I’m trying to pick everybody’s brain,” White said. “Just try and learn a little something from everybody.”

Listed at 210 pounds coming into the MLB Draft 3 years ago, Thomas White says he has now filled out to 247 https://t.co/lfMox2TiiX

— Fish On First (@FishOnFirst) February 12, 2026

Connecting with new teammates is essential to start on the right foot. White embraces his humility by trying not just to improve to be a great pitcher, but also to be a great teammate.

“I try to say hi to everybody every day and as many people as I can,” White said. “I think it’s going really well so far.” 

White’s Focus for 2026 Season

White has been focusing on building his body, but not too much. He also revealed whether or not he is adding new pitches to his game. 

“I tried to put on a little more weight,” White said. “This is probably the biggest I want to be. I’m just trying to get a little stronger, especially my upper half. I felt good about my lower half, but I think I could have added some strength at the top, so I tried to do that. As far as pitches, I’m just trying to be a little more consistent. I think all my shapes are pretty good.” 

He’s currently weighing 247 pounds, and he’s content with where he is right now. White is also proud of his progress last season in Triple-A and of moving up at each level. However, he’s not completely satisfied because he knows he could be better. That’s the mindset of a winner. 

“I was proud that I was able to move up a little bit and find success, a little bit of success at every level,” White said. “I think I could have done a little better at keeping my body healthier. The season wasn’t as good as the numbers suggest, at least for me personally. Towards the end, I had some back problems. So, my last six starts were a little tough.” 

In 2025, White had a record of 4-3 after starting in 21 games. He held a 2.31 ERA with a WHIP of 1.182 over 89.2 innings, working his way from Single-A all the way up to Triple-A Jacksonville in the season.

His back problems affected his mechanics, and he couldn’t put the ball where he wanted to. White did make some good mechanical adjustments this year, and he’s hoping to continue to build on that into the new season. Staying healthy will be vital for him to sustain long-term success in the majors. 

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