The right-hander allowed only an opposite-field single off the bat of Emil Brown, notching two strikeouts in his two innings and feeling as if he wanted to go longer.
"Oh yeah, I've been feeling that way the last couple of weeks," Harden said. "(Until Wednesday) I'd been limited to two simulated innings."
His next trip to the mound will be in Monday's Cactus League game against the Los Angeles Angels in Tempe. That will be Harden's first time facing hitters from another team since July, when he was shelved for the season with a strained right shoulder.
Like Joe Blanton, Harden is on an accelerated schedule to get him ready to start the second of two games in Japan on March 25-26 against the Boston Red Sox to open the regular season.
Harden mixed in his breaking ball and split-fingered fastball but stuck predominantly to fastballs and changeups. "He looked good," catcher Kurt Suzuki said. "He's looked good all along, and he feels good, which is the No.1 priority. He had good life on his fastball. He threw some changeups. His breaking ball is ready to go."
The four-inning game did feature a couple of other highlights: Right fielder Jeff Fiorentino threw out Mike Sweeney trying to stretch a single into a double. Left fielder Todd Linden made a sliding grab ranging to his right to rob Danny Putnam of a hit.
Reliever Joey Devine, acquired from Atlanta in the Mark Kotsay trade, looked sharp in his inning. He blew fastballs by Richie Robnett and Wes Bankston for called third strikes.
GEREN PONDERS ORDER: Manager Bob Geren shared his batting order for today's exhibition opener against the Milwaukee Brewers, though he was quick to point out it shouldn't be taken as a strong indicator, looking toward the regular season.
He'll bat right fielder Travis Buck leadoff, followed by second baseman Mark Ellis, first baseman Daric Barton, left fielder Jack Cust, designated hitter Dan Johnson, shortstop Bobby Crosby, catcher Suzuki, third baseman Jack Hannahan and center fielder Chris Denorfia.
Among the notable selections is Buck atop the order, though it's not exactly a surprise.
"I think he's a really good option right now," said Geren, who noted that Denorfia and Ellis are possibilities to lead off.
Trying Barton in the third spot obviously shows the A's feel the hot bat he swung in his September call-up is a sign of things to come.
"What he's done in his minor league career and did last September, he proved he deserves that shot," Geren said.
He added that outfielders Brown and Ryan Sweeney would start Friday against Milwaukee in the exhibition home opener and that Mike Sweeney would DH.
SHORT HOPS: Reliever Alan Embree has nursed a stiff back the past couple of days, but he threw 35 pitches Wednesday and is on track to pitch Friday. Blanton gets the start today, with Dan Meyer, Kirk Saarloos, Andrew Brown, Ryan Wing and Jay Marshall set to follow him to the mound.