Koehler is done before he started

PHILADELPHIA — Tom Koehler, the right-handed reliever signed by the Dodgers last winter as a potential replacement for setup man Brandon Morrow, underwent season-ending surgery on his right shoulder, manager Dave Roberts said. The operation probably will end Koehler’s tenure with the team before he could throw a single pitch this season.

Koehler was diagnosed with a strained anterior capsule after appearing in a spring-training game at Camelback Ranch on March 2. The Dodgers did not place a timetable for his return, but retained hope that he could come back. Those hopes were dashed when Koehler felt “a little something a few days ago which didn’t fit the progression of his rehab,” Roberts said.

The Dodgers signed Koehler, 32, to a $2-million contract with another $2 million in incentives, which Koehler will not reach.

“He was a guy who when we signed him this winter, we were all excited about it,” Roberts said. “Disappointing for him, for our ballclub, because I do think that he could have added a good element to our ’pen.”

Buehler returns

Walker Buehler will be recalled from the minors to start Wednesday against the Phillies. Buehler has not pitched in a game since July 13.

The team will carry six starting pitchers with Buehler active.

“The plan is for Walker to stick around a little bit,” Roberts said.

The Dodgers do not have a day off until Aug. 6, and can use a sixman rotation to keep their arms fresh.

Baez back Wednesday; Ryu to start rehab soon

Pedro Baez (biceps tendinitis) collected four outs for double-A Tulsa on Monday and is expected to rejoin the Dodgers on Wednesday, with the team desperate for arms after Tuesday's 16-inning loss.

Josh Fields (shoulder inflammation) is “still a little bit behind,” while Tony Cingrani (shoulder discomfort) “is moving forward,” Roberts said.

The Dodgers are hoping their relievers return to full health as they scan the trade market for other options before next Tuesday’s deadline.

Hyun-Jin Ryu (torn groin muscle) could begin a minor league rehab assignment this week. Ryu posted a 2.12 ERA in six starts before injuring himself May 1. He will require at least four outings to build up his pitch count, Roberts said. The organization does not view Ryu as an option for a relief role, given the maintenance required to heat up his surgically repaired shoulder.