Baltimore will try to stick to the same formula as it seeks an eighth win in 10 games Saturday in Oakland.
The Orioles (14-9) claimed a 3-0 victory Friday, quieting the Athletics' bats for a second straight night after a 10-2 win Thursday. Baltimore has a 1.91 ERA over the last five games, including a masterful performance Friday from Wei-Yin Chen, who gave up three hits in eight innings.
His outing helped drop the Orioles' opponent batting average to .228. That's among the best in baseball as is the bullpen's 2.31 ERA. Closer Jim Johnson improved to 9 for 9 in save opportunities by closing out Friday's win.
The Athletics (13-11), meanwhile, have lost seven of eight. Behind the slide has been a serious drop in power production. They hit 19 home runs during a 9-2 start, the most in the majors during that span, but have just five homers while going 4-9 since. They're homerless in five of the last seven.
The loss of Yoenis Cespedes, who had three home runs before succumbing to a strained left thumb April 12, also hasn't helped, though he's likely to be activated for Sunday's game.
Oakland received a good pitching performance Friday from Tommy Milone, who gave up only an unearned run over 6 2-3 innings. But the defense didn't lend much help as the Athletics committed a season-high three errors.
"When you are in close games like that - defensive miscues end up really costing you," manager Bob Melvin said. "It's maddening for us."
Chris Tillman (0-1, 5.23 ERA) will try to continue the Orioles' strong pitching. Though his numbers aren't impressive, he's coming off his best outing of the year, holding Toronto to one run and four hits over 6 2-3 innings in a 2-1 win.
"I was able to get ahead with my pitches early and my secondary stuff was there for me," he said. "I was able to pound the strike zone early and kind of make the pitches when I needed to."
Oakland starter A.J. Griffin (2-1, 4.50 ERA) will face Baltimore for the first time as he tries to shake off the worst performance of his young career. Griffin saw his ERA double after he surrendered a career-worst nine runs - seven earned - and eight hits over four innings in a 9-6 loss at Boston on Monday.
He hadn't surrendered more than five runs in his first 18 major league starts.
"It humbles you a little bit," Griffin said. "Obviously not going to go out there and be lights out every time."
Tillman didn't record a decision in his only previous start against the Athletics, giving up two runs and six hits in 4 1-3 innings May 27, 2011.