Dodgers pitchers Carlos Frias (back) and Chris Hatcher (oblique), both on the 15-day disabled list, will continue their rehab assignments with Triple-A Oklahoma City in the coming week.

Frias threw a bullpen session Sunday morning at Dodger Stadium and will start Wednesday for Oklahoma City. Hatcher is leaving today for Triple-A “and will be there for a while now,” manager Don Mattingly said.

Frias was placed on the 15-day disabled list July 1 with tightness in the lower right side of his back. Hatcher is on the 60-day disabled list because of a left oblique strain and cannot be activated before August 15.

They will not be joined by catcher A.J. Ellis, who is eligible to be activated from the disabled list Tuesday. Ellis had pain in his right knee when he was placed on the 15-day DL July 20, but that issue is long past.

“Knee-wise, I don’t think anybody thinks (a rehab assignment) is necessary,” Mattingly said of Ellis. “There were some discussions about him getting out and getting some at-bats. He was out four or five days, other than that he’s been hitting every day. So I think the consensus was he’s ready to go” Tuesday.

Austin Barnes has been the backup catcher to Yasmani Grandal in Ellis’ absence. He’s expected to be optioned to Oklahoma City when Ellis is activated Tuesday, the day the Dodgers begin a road trip to Philadelphia and Pittsburgh.