There’s still no timetable for Clayton Kershaw’s return to the mound for the Dodgers

The Dodgers did not have much to say Tuesday about Clayton Kershaw’s back injury. Kershaw and team officials met Monday with Dr. Robert Watkins, a back specialist, but neither the pitcher nor front-office executives have met with reporters since then.

Manager Dave Roberts said Kershaw is taking medication for his low-back strain and would not resume throwing until he is free of symptoms. Roberts declined to offer a timetable for Kershaw’s return but said Kershaw had a “Level 1” strain.

Strains are graded in terms of severity. The Dodgers hope Kershaw can return in four to six weeks, according to a person familiar with the matter, but the injury Roberts specified generally resolves itself in less time than that.

“A Grade 1 strain is the mildest kind of strain you can get,” said Dr. Jonathan Sum, assistant professor of clinical physical therapy at USC. “The timetable for that is fairly short.”

Sum, speaking generally because he has not examined Kershaw, said a longer timetable would not necessarily indicate a more severe injury than Roberts suggested. A longer time frame could reflect the need to return Kershaw to athletic competition rather than to, say, a desk job, and a comprehensive course of conservative treatment because of the herniated disk in Kershaw’s back.

Kershaw sat out 10 weeks last season as he rehabilitated the disk. Roberts said Kershaw has worked diligently to maintain back health while adjusting the rest of his strength and conditioning workload.

“There have been a lot of conversations on what he should do, can do, shouldn’t do, can’t do,” Roberts said. “He’s abbreviated his regimen from the offseason to in-season and curtailed a lot of the workload. Knowing Clayton, no one works harder.

“There are going to be unforeseen things that do happen when you’re a professional athlete that you can’t guard against. I think our guys have done everything they can to minimize it, to prevent it. It is what it is right now. They’re going to get him back as soon as they possibly can.”

Sum said the presence of the herniated disk increases the risk of future injury.

“It requires a lot more muscle strength, core stability, to make sure that disk stays nice and stable,” Sum said. “The disk itself promotes stability. When you have a weakening of the outer ring of the disk, it makes it more susceptible for a return injury.”

Once the immediate injury is resolved and Kershaw returns to action, his back history will provide an intriguing backdrop to the 2018 season. Kershaw turns 30 next year.

His effectiveness upon his return would help inform two important decisions: whether Kershaw exercises his right to opt out of his contract after next season, walking away from two years and $65 million, and how far the Dodgers would extend themselves in a long-term offer to keep him.

Brock Stewart to start

With Kershaw out, the Dodgers plan to insert Brock Stewart into their starting rotation Wednesday. Roberts said he expected Stewart to make at least two starts.

Stewart has thrown 13 scoreless innings, all in relief, since the Dodgers recalled him from triple-A Oklahoma City last month. He made four minor league starts before his recall but did not make more than 52 pitches or complete four innings in any of them, so his start Wednesday is expected to be a brief one.

Stewart, 25, started five games for the Dodgers last season, most memorably pitching five innings in a 1-0 victory over Jon Lester and the Chicago Cubs.

Adrian Gonzalez update

Roberts said first baseman Adrian Gonzalez (herniated disk) probably would start a minor league rehabilitation assignment next week and would need “a week, at the minimum” before the Dodgers would activate him. He has not played since June 11.

The Dodgers want to see whether Gonzalez is healthy and productive before committing to how they might use him upon his return, but one option would be to move Cody Bellinger from first base to left field and Chris Taylor from left field to second base, displacing Logan Forsythe from the starting lineup. The Dodgers also could deploy a platoon in which Gonzalez plays against right-handers and Forsythe against left-handers.

Chase Utley started Tuesday and has started three of the last six games at second base. Forsythe is batting .238 with three home runs, but is batting .188 with a .534 OPS against right-handers and .338 with a .996 OPS against left-handers.

bill.shaikin@latimes.com

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