The Athletics have placed A.J. Puk on the 10-day injured list with strained left biceps, the team announced. In corresponding moves, Trevor Rosenthal was moved to the 60-day injured list and Deolis Guerra has been selected from the alternate site.

There’s not much to say about Puk landing back on the injured list after just one appearance. The towering southpaw has struggled to stay healthy. He missed all of the shortened 2020 season because of a shoulder strain. Hopefully, this stint on the IL will be a short one for the 25-year-old, who remains one of the most promising arms in the A’s organization and a potential difference-maker for the 2021 season.

The Rosenthal news is no less dispiriting, though given the recent diagnosis, it was to be expected. Rosenthal is likely to need thoracic outlet surgery, which carries a recovery time of at least 12 weeks. The A’s signed Rosenthal to a one-year, $11MM deal this winter to serve as the replacement for departed-closer Liam Hendriks.

Guerra, 31, is a right-hander out of Venezuela. He made nine appearances for the Phillies last year while previously suiting up for the Brewers, Angels, and Pirates. Since 2015 he has made 83 total appearances spanning 103 innings with a 4.81 ERA/4.78 FIP. It has been a couple of years since his best showing with the Angels from 2016-17, however.