A's reliever Trevor Rosenthal to have season-ending hip surgery

Athletics reliever Trevor Rosenthal tore a labrum in his hip and will require surgery, manager Bob Melvin told reporters (including Shayna Rubin of the San Jose Mercury News). He won’t pitch at all in 2021.

It will go down as a completely lost season for Rosenthal, who began the year on the injured list with shoulder soreness. Further evaluation revealed he’d need to undergo surgery to correct thoracic outlet syndrome, which he had in early April. The hope had been that Rosenthal would be able to return at some point in August, but his new injury obviously ends that possibility.

It’s a horrible development for Rosenthal, who has had a few recent seasons derailed by injury. The former Cardinals closer suffered a UCL tear in 2017 that required Tommy John surgery. He lost all of 2018 rehabbing and looked nothing like himself when he returned the following season. Rosenthal walked an astounding 30.6% of opposing hitters with the Nationals and Tigers that year, forcing him to settle for a minor-league contract with the Royals over the 2019-20 offseason.

Remarkably, Rosenthal completely reversed his fortunes to be among the top relievers in baseball last year. He cracked the Kansas City roster and pitched well enough to attract the interest of the contending Padres, who acquired him in advance of the trade deadline. Between the two clubs, Rosenthal pitched to a 1.90 ERA over 23 2/3 innings, striking out a whopping 41.8% of opponents while walking a lower than average 8.8%.

That positioned Rosenthal as one of the top free-agent relievers in last winter’s class. He lingered on the market until late February, when the A’s stepped up and landed him on a one-year, $11 million contract. It was a surprising reversal from Oakland’s otherwise thrifty offseason, which included the team declining to make $18.9 million qualifying offers to star reliever Liam Hendriks and shortstop Marcus Semien.

The A’s will ultimately get no return on that investment, as Rosenthal’s injury woes will keep him from donning the green and gold in a meaningful game. His contract contained a series of deferrals — Rosenthal is making $3 million in 2021, followed by $3 million in 2022 and $5 million in 2023 — but he’ll again reach the open market this winter.

It’s not yet clear whether Rosenthal is expected to be ready for spring training in 2022. Considering Rosenthal's injury-wrecked campaign, it’s plausible he’ll need to throw in front of scouts to demonstrate his health before he lands a new deal. Rosenthal is still just 31 years old and was brilliant when last able to take the mound, so it stands to reason there’ll be interest from teams if/when he works his way back to full strength.