ST. PETERSBURG — The Rays placed key reliever Tyler Wells on the 15-day injured list with right forearm tightness before their series opener against the A’s at Tropicana Field, sidelining the 32-year-old setup man for the remainder of the regular season as Tampa Bay chases its first American League East title since 2021.

Wells had posted a 1.50 ERA in 14 relief appearances since joining the Rays from the Orioles at the Trade Deadline, solidifying the setup mix in front of All-Star closer Bryan Baker. His IL assignment was made retroactive to Sunday, but imaging conducted Monday revealed no structural damage.

“Hoping that it’s just a minimum stint,” Wells said. “Nothing too bad, but we got everything checked out by multiple doctors. Everything looks really, really good. There’s no structural damage or anything like that. That is no concern whatsoever. So, overall, just got the best news possible.”

Rays manager Kevin Cash called it a “tough call” but said the club prioritized Wells’ long-term health. “I’m happy that he’s optimistic. That gives us more optimism,” Cash said. “Some forearm tightness that we felt like we’ve really got to kind of manage and get it calmed down. He’s been such a big part of our club and our bullpen since being acquired, so we’ll try to get it calmed down and go from there.”

Wells said he felt no issues while pitching Saturday but noticed tightness afterward. “Super frustrated. I mean, the timing obviously couldn’t have been worse given the circumstances,” Wells said. “But at the same time, too, this allows me to get ready for the postseason and really make sure that I’m feeling right and, I think, being able to contribute there and hopefully make up for the time missed during these critical games.”

The bullpen has taken multiple hits, with Wells joining Manuel Rodríguez and Garrett Cleavinger on the injured list. Rodríguez began a rehab assignment with Triple-A Durham on Sunday and is in line to return before the regular season ends. The Rays recalled right-hander Alex Cook from Durham to replace Wells and have turned to prospects Ty Johnson and Brody Hopkins to fill earlier bullpen spots, with both expected to audition for postseason roles.

In a corresponding move, the Rays reinstated outfielder Jake Fraley from the 60-day IL. Out since May with a hernia, Fraley carried a .690 OPS with two home runs in 28 games before the injury and had been rehabbing with Triple-A since Aug. 25. Victor Mesa Jr. stepped into Fraley’s right-field role during his absence and became one of Tampa Bay’s most valuable players, so Cash said Fraley could contribute off the bench. “I’m just excited to help in any way I can. I’m not putting any expectations on it,” Fraley said.

The AL-leading Rays face additional roster decisions ahead, with shortstop Taylor Walls listed as “day to day” with a right hip flexor strain and infielder Ben Williamson beginning a rehab assignment with Durham on Tuesday night after a right hamstring strain.