For instance, when Frank Thomas drew a walk to put runners on first and second with two outs in the 10th inning of a 1-1 game Monday, Geren knew Brown was the man he wanted at the plate.
Brown delivered, ripping the first pitch he saw from the Baltimore Orioles' Jim Johnson into left-center and scoring Daric Barton from second to give the A's a 2-1 victory before 10,128 fans at McAfee Coliseum.
"When Frank walked, I was happy to see him up there," Geren said of Brown.
That capped a 3-for-4 night for Brown, who entered Monday second in the American League with 26 RBI.
He's finding other ways to contribute too. Brown ended the top of the first when he caught Melvin Mora's fly in right field and fired a one-hopper to first to double off Nick Markakis.
But it's his performance with runners in scoring position that has kept him in the lineup regularly, as Geren shuffles his other outfielders based on pitcher matchups.
"I try to be as 'selective-aggressive' as I possibly can," Brown said. "What I mean is, get something in the strike zone."
The win evened the A's record on this six-game homestand at 2-2, and they remained one game behind the first-place Los Angeles Angels.
The only shame on this night was that starting pitcher Dana Eveland didn't walk away with the 'W.' The left-hander, who hadn't completed six full innings in his previous four starts, turned in a sterling seven-plus innings.
Closer Huston Street entered in the ninth not having blown a save since the season opener March 25 against the Boston Red Sox in Tokyo. But Street allowed a leadoff double to Mora and walked Aubrey Huff. With runners on the corners and one out, former Athletic Ramon Hernandez hit a slow grounder to short. Bobby Crosby fielded it, considered going home to try to nail Mora but threw to first as Baltimore tied the game 1-1.
Chances were slim Crosby could have turned two on the play as well.
"If he forced that throw (home), it could have hurt," Geren said. "He went about it the right way."
The damage Hernandez's slow grounder did was typical of the offense Monday.
The A's mustered just three hits through the first six innings against Baltimore starter Garrett Olson, who matched Eveland's impressive outing.
Oakland broke a scoreless tie on the strength of two tappers in the seventh that didn't make it to the outfield grass. With two outs, Jack Hannahan beat out a soft grounder to the left side to load the bases. Then Rajai Davis tapped a ball to the right side. Baltimore first baseman Kevin Millar fielded it, but Orioles reliever Jamie Walker was slow to cover the bag and the fleet-footed Davis easily reached base to give the A's a 1-0 lead.
Alan Embree did a fine job holding the lead in the eighth and getting the ball to Street. Embree came on with runners on second and third and one out. He retired Brian Roberts on a shallow fly to right-center and Markakis on a grounder to short.
Monday's game was the first time Eveland pitched into the seventh inning since April 10, his second start of the season. Through the first seven innings Monday, he allowed just one runner as far as second base. Eveland said he had a decent changeup and slider, but he relied greatly on a fastball that consistently reached the lower 90s.
"It wasn't locating great, so I just reached back and let it eat," Eveland said of his fastball.
Contact Joe Stiglich at firstname.lastname@example.org.
A'S 2, ORIOLES 1