The Rangers are bringing a familiar face back to Texas, signing right-handed reliever Mason Thompson to a minor league deal. It's a homecoming for the 6-foot-6 Round Rock native, who’s expected to be in big league camp later this month as a non-roster invitee. And while the numbers haven’t always been pretty, there’s enough in Thompson’s profile to make this a low-risk, potentially savvy pickup for a bullpen that’s still very much under construction.
Thompson, a third-round pick by the Padres back in 2016, has logged time in the majors with both San Diego and Washington over the past four seasons. His career ERA sits at 5.21 across 114 big league innings - a number that took a big hit in 2025, when he allowed 16 earned runs in just 10 2/3 innings for an ERA north of 11. That rough stretch also extended to the minors, where he posted an ERA over 6.00 in limited work.
But it’s important to put that season in context. 2025 marked Thompson’s return from Tommy John surgery, which sidelined him for the entire 2024 season. Rust is expected, and command issues are often the last thing to return for pitchers coming off that kind of layoff. So while the surface stats were ugly, there’s a case to be made that the real evaluation window starts now.
Before the injury, Thompson showed flashes of being a useful bullpen piece. From 2021 through 2023, he pitched 103 1/3 innings with a 4.53 ERA.
His strikeout (17.7%) and walk (10%) rates weren’t anything to write home about, but his 51.1% ground-ball rate stood out. That’s the kind of profile that can play if the command sharpens and the stuff ticks back up.
Speaking of stuff, even in his return from surgery, Thompson’s sinker was still averaging 95 mph - a good sign for a pitcher trying to regain form. He also mixes in a four-seamer at similar velocity, a mid-80s slider, and an occasional changeup that sits in the upper 80s.
The velocity dip from his pre-surgery days was noticeable, but not alarming. If he can regain a tick or two this spring, he could find himself back on the radar.
For the Rangers, this is the kind of depth move that makes sense. Their 2025 bullpen was largely pieced together with short-term deals, and several of those arms are now gone.
So far this winter, they’ve followed a similar blueprint - re-signing Chris Martin and adding Jakob Junis, Alexis Díaz, and Tyler Alexander on one-year contracts. They also claimed right-hander Michael Otañez off waivers.
Thompson, if invited to camp as expected, will be the most experienced bullpen arm among the non-roster invitees. That doesn’t guarantee anything, but it does give him a leg up in what figures to be a wide-open competition for the final few bullpen spots.
At 28 years old and with big league innings under his belt, Thompson’s path back to the majors will depend on how quickly he can shake off the rust and show that the pre-injury version - the one who kept the ball on the ground and flashed mid-90s heat - is still in there. For a Rangers team looking to build a bullpen on the fly again, that’s a gamble worth taking.