CSN Bay Area

A's closer Sean Doolittle has a slight rotator cuff tear in his throwing shoulder and will miss the start of the regular season, the team announced Friday.

Doolittle, an All-Star last season, first felt soreness after starting his offseason throwing program in December, according to Oakland assistant general manager David Forst. When his shoulder didn't get better after a few throwing sessions, the A’s sent him to Phoenix-based orthopedist Dr. Doug Freedberg, and an MRI revealed the tear.

The left-hander received a platelet-rich plasma injection last Friday in an effort to relieve the inflammation and irritation in his shoulder. Doolittle, 28, won’t begin any rehab until the swelling is gone, so right now there's no timetable for when he might return.

With pitchers and catchers set to report in 3½ weeks, it’s a significant blow for an A’s team that’s relied greatly on a lock-down bullpen in qualifying for the playoffs three consecutive seasons.

“It’s disappointing for Sean,” Forst said in a phone interview. “We have some time to figure things out, and we’ll get him back at some point.”

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The A's recently acquired two-time All-Star setup man Tyler Clippard from Washington for shortshop Yunel Escobar, and though Forst said that trade was made independent of Doolittle’s condition, the move seems especially important given Friday’s news.

Clippard saved 32 games in 2012 while getting a shot to close for the Nationals, so he’s an obvious candidate in save situations while Doolittle is sidelined. Ryan Cook had 14 saves as a rookie in 2012 and Dan Otero and lefty Fernando Abad could also be ninth-inning considerations. It’s unknown if the A’s will consider going after another reliever.

“We do like our options and we’ll spend spring training figuring out what’s the best lineup for the back of the bullpen,” Forst said. But he added that when a closer goes down, “it hurts your sixth, seventh and eighth-inning depth.”

Doolittle, who signed a five-year, $10.5 million contract last April, went 2-4 with a 2.73 ERA last season and 22 saves, which set an A’s record for lefties. But Forst said Friday that Doolittle did pitch through some shoulder discomfort last year. After the long offseason layoff, his shoulder started bothering him again when he cranked up his throwing in preparation for this season.

Forst said that Freedberg and team orthopedist Dr. Will Workman agree that surgery does not appear necessary for Doolittle.