Athletics 2, Orioles 1: Coco Crisp hit a lead-off homer in the ninth inning to lift visiting Oakland over Baltimore and even the three-game set at one win apiece.

Crisp smashed a 3-1 curveball from reliever Darren O’Day (5-3) well over the right-field fence for his third homer in as many games. The tiebreaking shot gave the Athletics a 2 1/2-game lead over Cleveland and a three-game edge over the Orioles in the competition for the American League’s second wild-card spot.

Jarrod Parker (10-6) allowed one run and five hits in eight innings to claim his eighth straight victory and stretch his string of unbeaten starts to 16. Grant Balfour struck out two in a perfect ninth for his 32nd save in 33 opportunities as Oakland moved within 2 1/2 games of first-place Texas in the AL West.

Ryan Flaherty hit a one-out homer to right in the third inning to give Baltimore the early lead. Oakland tied the game in the sixth on doubles by Crisp and Jed Lowrie.

Baltimore’s Chris Tillman matched his career high with nine strikeouts and allowed one run and three hits in eight innings. The Orioles slipped to 5 1/2 games behind the Boston Red Sox in the AL East.

GAME NOTEBOOK: Lowrie went 2-for-3 with a walk and is 9-for-25 with four doubles and two triples during a six-game hitting streak. … Orioles OF Nick Markakis went 1-for-4 and has 31 consecutive singles since his last extra-base hit on July 19. … Oakland OF Josh Reddick (wrist) returned from a one-game absence and went 0-for-3 with two strikeouts.