The Arizona Diamondbacks moved Jordan Montgomery to the bullpen as the veteran left-hander continues to struggle in his first season with the team.

Montgomery, one of baseball's top free agents this offseason, didn't sign with the Diamondbacks until late March, ultimately landing a one-year, $25 million deal that includes a vesting option for 2025.

His agent at the time, Scott Boras, negotiated several similar short-term deals for his top free agents late in the offseason.

Montgomery ultimately fired Boras shortly after he signed with Arizona, and he voiced his displeasure with how things were handled Friday before Arizona took on the Boston Red Sox, one of the teams interested in signing him.

"I had a Zoom call with [the Red Sox], that's really all I know. It went good," Montgomery told the Boston Herald. "I don't know, obviously Boras kind of butchered it, so I'm just trying to move on from the offseason and try to forget it."

Because of the late signing, Montgomery didn't have a formal spring training and didn't make his first start for Arizona until April 19. He has a 6.44 ERA in 19 starts this season.

Manager Torey Lovullo called the decision to move Montgomery to the bullpen "agonizing" but one that made sense given Ryne Nelson's recent run of strong performances, which continued Friday night when he gave up just two runs and five hits while striking out seven in a 12-2 win against the Red Sox.

Montgomery has primarily been a starter in his eight big league seasons.

Because he already has made 19 starts this season, the 2025 vesting option in his deal became guaranteed at $22.5 million, per details of his contract reported at the time he signed it. If he were to make 23 starts, that figure rises to $25 million.

"We have 30-something games left," general manager Mike Hazen told reporters, according to the Arizona Republic. "We're trying to win every single game. I've pushed Torey to make the best decisions for the team every single night to put us in a chance to win. Period. I don't care about anything else. I told him, 'We'll deal with anything we have to.'"