Dodgers starter Zack Greinke, who broke his collarbone a month ago, reported no lingering signs of his injury after starting his rehab assignment Friday night with Class A Rancho Cucamonga.

Greinke, who pitched 4 1/3 innings Friday, could be ready to return from the disabled list as early as Wednesday at home against the Nationals.

"It won't be his decision," manager Don Mattingly said. "It's not so much that he's ready to pitch here, it's that they're willing to take the risk of everything that could happen while he's pitching here. I think we would all like it to be here. But I'd also like him to be totally ready."

Greinke told MLB.com that he is close to 100 percent.

"I'll be close to 100 percent, physically," Greinke said. "Pitching-wise, close to 100 percent. I'm probably five starts until I'm 100 percent pitching-wise and they don't want to wait that long."