SAN FRANCISCO -- Los Angeles Dodgers left-hander Hyun-Jin Ryu has elected to have surgery on his injured pitching shoulder, a source confirmed, casting doubt on his ability to throw for the team this season.

Hyun-Jin Ryu will have shoulder surgery, but whether he misses the rest of the 2015 season is up in the air. AP Photo/Jeff Roberson

The latest MRI on Ryu did not show a torn labrum or any obvious structural damage, so the operation would be aimed at discovering and cleaning up whatever is causing the inflammation that has kept him on the disabled list all season.

Ryu's first attempt to return without surgery in March was aborted when he felt tightness in the shoulder during a bullpen session.

News of Ryu's decision first surfaced in Korean newspapers.

The Dodgers haven't announced Ryu's surgery, but Dodgers president of baseball operations Andrew Friedman said surgery is being discussed. Ryu was scheduled to consult with team physician Neal ElAttrache Tuesday evening. Friedman also acknowledges he is no longer thinking Ryu will be part of the team's rotation this season, "because it's more helpful to err on that side rather than err on the more positive side."

"It hasn't progressed as quickly as we all hoped, and he's worked extremely hard to get back. It just isn't happening as quickly as he would like," Friedman said. "It's not a totally clear-cut, black-and-white issue. It's more involved than that. We have an excellent doctor in ElAttrache and a very good medical department ,and everyone is putting their heads together to see what makes the most sense."

Ryu would be the second Dodgers starter to be lost to surgery. Brandon McCarthy had undergone Tommy John elbow reconstruction and is expected to be out until around the 2016 All-Star break.

Ryu's decision could send the Dodgers into a full-scale search for a starting pitcher, though they have had surprisingly good results internally. Carlos Frias -- who will try to extend his record to 4-0 on Tuesday night in San Francisco -- and Mike Bolsinger have given the Dodgers solid spot starts.

The Dodgers also have Brandon Beachy under contract for $2.75 million as he tries to work his way back from a second Tommy John surgery. Beachy, who threw a bullpen session Monday, is expected to go on a minor league rehab assignment soon, and his return, presuming he has no setbacks, is expected in June.

"He's making progress," manager Don Mattingly said. "Mentally he's moving forward. He's getting closer and closer to games."

Ryu is 28-15 with a 3.17 ERA in two seasons for the Dodgers.