LOS ANGELES -- Zack Greinke's ailing right arm is structurally sound and the Houston Astros are still hopeful that he can contribute again at some point this postseason, manager Dusty Baker said Wednesday morning, hours before Game 3 of their American League Division Series.

Greinke, who hasn't pitched since Game 1 of the wild-card series eight days ago, threw about 15 pitches off flat ground at low intensity after Tuesday's 5-2 win over the Oakland Athletics, then spent a long time chatting with Astros pitching coach Brent Strom. Strom told Baker that the session went "pretty good," according to Baker.

If the Astros win Wednesday and advance to their fourth consecutive AL Championship Series, they will have three days off before the start of the next round at Petco Park in San Diego. But Baker also didn't rule out the possibility of Greinke starting in the ALDS if it gets extended.

Greinke, 36, hasn't completed six innings since Sept. 8 and has a 5.79 ERA over his past four starts. Baker said after Tuesday's game that Greinke is dealing with "some soreness in his arm" but didn't go into further details.

The ailment is part of why the Astros gave the Game 3 start to Jose Urquidy, who has allowed only eight earned runs over his past 30 1/3 innings.

"I'm hoping that we win today's game and then we'll have a few days off to rehab and try to feel better before next [round]," Baker said. "But we have to win this game first."