The Rays shuffled their bullpen again after Tuesday's game, sending down struggling LHP Jose Alvarado along with RHP Austin Pruitt to Triple-A Durham, and turning next to LHP Adam Kolarek, who will make his major-league debut at age 28.
Pruitt seemed likely to be sent down to make room for LHP Blake Snell, who is rejoining the rotation, with RHP Erasmo Ramirez going to the bullpen.
Alvarado's demotion was warranted as the 22-year-old rookie has been struggling mightily since an impressive first month after his unexpected promotion from Double-A, allowing runs in five of his last six outings and taking three losses.
The Rays didn't have any obvious replacements, but are turning to Kolarek, who had been pitching well for them at Triple-A Durham, posting a 1.36 ERA for 33 innings over 31 games, allowing 26 hits and 12 walks with 29 strikeouts.
Kolarek split 2016 between Durham and Double-A Montgomery, got a spring training invite from the Braves but got let go and ended up re-signing with the Rays at the end of the spring. He came up in the Mets organization and spent six years with them, getting to Triple-A for two games in 2013.
To make room for Kolarek on the 40-man roster, the Rays transferred CF Kevin Kiermaier (right hip fracture) from the 10- to the 60-day DL, meaning he can't return before Aug. 8.