LOS ANGELES -- Dodgers left-hander Clayton Kershaw was placed on the 15-day injured list with low back pain on Friday, a day after he exited the club’s 5-3 win over the Giants before the fifth inning.

“Obviously, given the soreness, where we’re at, we decided to IL him,” said Dodgers manager Dave Roberts. “I don’t know the results yet of the MRI, but, hopefully, it’s going to be shorter than longer.”

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Roberts said he was hesitant to put a timetable on Kershaw, who woke up sore on Friday, but the manager said it was “fair” to assume the left-hander would be out closer to a month. Kershaw has battled back injuries in five of his last seven seasons. Each time, the future Hall of Famer has not missed fewer than three weeks.

The Dodgers recalled right-hander Reyes Moronta to take Kershaw’s place on the active roster.

Earlier this year, Kershaw missed a month with right SI joint inflammation, which flared up during a cross-country flight. Roberts said this back injury is different than that one.

“As I recall, the injury before was more on the right side and I think back, hip related,” Roberts said. “This one is more on the left side. And, again, I think it’s still back, hip related, but I haven’t seen or heard about the MRI. This is just my conversation with Clayton.”

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Kershaw suffered the injury as he warmed up before the fifth inning on Thursday. He said he felt fine over the first four innings but felt something tighten up after his penultimate warmup throw. He then tried to throw one more to test the back but immediately motioned over to the Dodgers’ dugout. He left the game with trainer Thomas Albert.

After the game, Kershaw was understandably frustrated. During his last back issue, he hoped that would be the last time he dealt with an injury this season. When healthy, Kershaw has been one of the Dodgers' best pitchers, posting a 2.64 ERA over 15 starts.

“He’s certainly frustrated,” Roberts said. “But there’s nothing we can do about it. I think his only focus is to do what we can to get him back as soon as possible, and healthy.”

Though Moronta replaced Kershaw on the active roster, Roberts said that adding a reliever is more of a short-term solution. Once Kershaw’s spot in the rotation is up, the Dodgers likely will turn to right-hander Ryan Pepiot, who has a 2.76 ERA in four starts this season. 

The Dodgers didn’t trade for a starting pitcher before the Trade Deadline on Tuesday. They showed heavy interest in Marlins right-hander Pablo López. But instead, they traded away right-hander Mitch White -- their best depth piece. 

Dustin May, who pitched four innings with Triple-A Oklahoma City during his rehab assignment on Wednesday, will need at least one more outing in the Minors -- most likely two -- before being a candidate to take any starts Kershaw might miss. 

The Dodgers are optimistic that Blake Treinen, Tommy Kahnle, Brusdar Graterol, Danny Duffy, May and Kershaw all return in time to get them ready for a postseason run.