Reliever Tom Koehler, sidelined all season because of a right-shoulder strain, suffered a setback last week and has been shut down.

The right-hander was preparing to throw another bullpen session Thursday when he felt some discomfort in the shoulder while throwing a curveball.

Koehler, who was expected to replace Brandon Morrow as the team’s primary setup man, was hoping to return around the All-Star break. Roberts said that timetable has been pushed back to “sometime in August.” The Dodgers hope Koehler can resume playing catch this week.

“He was using his entire [pitch] mix and was starting to ramp it up a bit when he threw a curveball that didn’t feel great coming out,” Roberts said. “So we wanted to back off a bit, slow him down and then restart him.”


Left-hander Hyun-Jin Ryu, sidelined since May 3 because of a left-groin strain, also suffered a minor setback Saturday when trainers stopped his bullpen session after 20 pitches because of tightness in his groin. Ryu is expected to throw in the bullpen this week.

“I wouldn’t say it’s a setback,” Roberts said. “He felt a little tightness. Not pain. Our advice to him, as with any player, is if you feel anything that’s a little bit uncomfortable as you’re coming back, let us know and we can shut it down and go from there. There’s no reason for him now to push through it.”