Dodgers’ Tom Koehler to start season on disabled list

The Dodgers’ most significant acquisition in free agency walked into the clubhouse in a sling on Saturday. Tom Koehler will start the season on the disabled list, and the Dodgers reliever said he could miss weeks or months with a strain in his right shoulder.

“We’re optimistic he’ll be back this year,” Manager Dave Roberts said.

Said Koehler: “I came here to help this team win a World Series. If that starts a little later in the season, so be it.”

Koehler was the only free-agent pitcher the Dodgers signed to a major league contract, and he had been projected as a primary setup man for closer Kenley Jansen.

“He’s a guy that we were counting on for high-leverage situations,” Roberts said Friday. “To lose him for any extended period of time, yeah, that’s a big blow.”

Andrew Friedman, the Dodgers’ president of baseball operations, said Saturday that the injury did not make it more likely that the team would acquire a reliever via trade or free agency, in part because the timetable for Koehler’s return is unclear and in part because the search for depth is ongoing.

“Deals that made sense three days ago will still make sense,” Friedman said. “And I don’t think the opposite is true: I don’t think something is going to make more sense that didn’t three days ago. “

The list of available free-agent relievers — including Joe Blanton, Drew Storen and Huston Street — is not inspiring.

In addition to Jansen, Roberts listed right-handers Pedro Baez and Ross Stripling and left-handers Scott Alexander and Tony Cingrani as locks for what is expected to be an eight-man bullpen.

Right-handers Josh Fields, Wilmer Font, Yimi Garcia, Zach Neal and left-handers Adam Liberatore and Edward Paredes are among the candidates to fill the remaining bullpen spots.

The Dodgers had 14 pitchers make at least 10 relief appearances last season. The one that emerged as their primary setup man, Brandon Morrow, started the season in the minor leagues.

“It’s similar to the last couple of years,” Friedman said. “We didn’t know exactly, standing here in spring training, who would be pitching meaningful innings for us. But we knew we had enough options and interesting guys with compelling upside stories that we would figure it out. And it’s not that different right now.

“That also assumes you can accurately predict who are going to be the good relievers going into each year, but you can’t. So you appreciate the volatility of it, and you have a lot of really interesting, high-upside guys, and you sift through it.”

Indeed, the Dodgers signed Koehler for $2 million, with the intention of converting him from a struggling starter into a dominant reliever. The Colorado Rockies spent $104 million last winter on relievers Wade Davis, Bryan Shaw and Jake McGee, three of the 13 relief pitchers that signed for at least $10 millon.

The volatility in the performance of relief pitchers generally makes the Dodgers reluctant to spend heavily on them.

“We also signed a closer for $80 million,” Friedman said, chuckling. “So it’s case by case.”

Koehler left Friday’s game and told Roberts that his bicep had “locked up.” Koehler said Saturday his arm “progressively got worse” during the inning he pitched but wanted to try to complete the inning. He left after four batters.

“I knew I couldn’t keep going,” he said.

Koehler said the injury was diagnosed as a mild strain of the anterior capsule, with his return dependent on how rapidly the strain heals.

“It could be weeks. It could be months,” he said. “Right now, it’s a little bit of an unknown.

He added: “The surgery option was not mentioned. I will be pitching this year. It’s just a matter of when.”

That, he said, was what kept him relatively upbeat.

“It’s a good team here,” he said. “They’re going to be able to pick up the slack for sure. My goal right now is to get back and just contribute to winning a world championship.”

UPDATED 10:40 a.m. — This report has been updated with comments from Dodgers manager Dave Roberts and president of baseball operations Andrew Friedman.

bill.shaikin@latimes.com

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