PITTSBURGH -- Clayton Kershaw will make a rehab start for Triple-A Oklahoma City on Saturday before returning to the Dodgers' starting rotation, manager Dave Roberts said after Kershaw's successful four-inning simulated game on Monday.

"He's getting close," Roberts said after Kershaw threw 55 pitches to test the strained lower back that put him on the disabled list July 24. "There's zero chance [of Kershaw starting for the Dodgers on Saturday instead]. There's a level of intensity that continues to heighten, from bullpen to simulated game to Triple-A where you're competing. You continue to ramp up as far as intensity, and crossing that marker makes everyone feel better."

An impatient Kershaw believes the rehab start is unnecessary.

"Health-wise, I could have pitched in the big leagues 10 days ago. But that's not the plan, obviously," Kershaw said. "I don't feel I missed much time. I kept throwing all the way through. I guess it's the luxury we have as a team.

"You can't simulate a Major League game. You've just got to do it. Sim games are really hard. You try to create intensity, but you can't and it's really not a good recipe, but I guess it's what you have to do."

Roberts said he understands Kershaw's desire for a fast return, but he's sticking with the original plan.

"For us, I think that's the way it should be as far as his potential to pitch for us," said Roberts, "but taking all the information from the medical staff, that's the prudent decision and we think the right thing to do."

Chase Utley and @kikehndez get some ABs in against @ClaytonKersh22 in a simulated game. #LetsGoDodgers pic.twitter.com/VhIyfpOyxP — Los Angeles Dodgers (@Dodgers) August 21, 2017

Kershaw faced Enrique Hernandez , Chase Utley and batting coach Turner Ward in the sim game that was observed by Roberts, in addition to pitching coach Rick Honeycutt and a handful of teammates, who split time staring at the solar eclipse with protective glasses.

Austin Barnes caught the sim game, and he said Kershaw threw all of his pitches and there was "no tail-off" as the session progressed. Kershaw appeared typically overpowering, although he seemed annoyed with a lack of command at the end of the third inning.

"It's just Kershaw being the perfectionist he always is," said Barnes. "When the ball doesn't go exactly where he wants it, that's what makes him so good. From the bullpen, looks like the same Kershaw to me."

Honeycutt said Kershaw's Monday session was changed from three innings to four to work in an extra up and down with rest in between innings, which Honeycutt believes is more critical to coming back from an injury than merely a pitch count.