The right-hander makes his first appearance since breaking his collarbone a little more than a month ago as he faces the visiting Washington Nationals on Wednesday night.
Greinke (1-0, 1.59 ERA), who underwent surgery two days after suffering the injury during a benches-clearing brawl versus San Diego on April 11, was originally expected to miss two months but will be activated from the disabled list for the finale of this three-game set.
"He feels like he's ready," manager Don Mattingly told the Dodgers' official website. "His stuff kind of tells us he's ready. He wants to pitch."
While Greinke made one rehab start at Class A Rancho Cucamonga on Friday when he allowed three earned runs in 4 1-3 innings, he doesn't not seem too concerned with any potential problems associated with his quick comeback.
"I'm sure there's a lot of risk every day," Greinke said. "If it makes sense, you do it. If I didn't feel ready, I wouldn't do it. If it was 50/50, you don't do it. I say it's well worth the risk we're taking.
"If everyone in baseball had the same feeling I have, everyone would be playing. It's nothing superhero-ish. If you felt what I feel, you'd do the same thing."
It might take some time for him to regain the form he showed while allowing two runs and one walk in 11 1-3 innings during his first two starts for Los Angeles (16-22).
"I don't know how long it will take to be 100 percent crisp, but I feel good throwing all my pitches," he said. "Stuff is coming out crisp, nothing is holding me back. I'm ready to go."
The Dodgers have gone 10-19 since the injury to Greinke, who is 2-0 with a 1.93 ERA in two starts against the Nationals franchise.
It seems likely he won't have to face Bryce Harper for the first time. The young star sat out Tuesday and probably will miss the series finale after he cut his chin and hurt his shoulder slamming into the right-field wall trying to make a catch in a 6-2 victory over the Dodgers on Monday.
"His shoulder, (left) knee and head took the brunt," manager Davey Johnson said. "I'd say I'm more worried about his shoulder and his knee than I am about the stitches in his chin."
The offense struggled without Harper on Tuesday. Washington fell 2-0 to the Dodgers as Andre Ethier's two-out, two-run single in the third inning was the difference.
Ryan Zimmerman had three of the Nationals' five hits and is 10 for 22 over the last six games. Washington (21-18), though, has dropped three of four and has totaled three runs in those defeats.
Scheduled Nationals starter Ross Detwiler (2-3, 2.53) snapped a personal three-game losing streak Friday when he gave up two runs without a walk in 6 2-3 innings of a 7-3 win over the Chicago Cubs.
The left-hander is 1-1 with a 3.57 ERA in three starts versus Los Angeles, which has won three of four following an eight-game skid.