OAKLAND, Calif. -- Left fielder Robbie Grossman hit a tie-breaking, two-run single in the top of the 11th inning, and the Houston Astros held on for a 5-4 victory Friday night against the Oakland Athletics at the O.co Coliseum.

A's left-hander Eric O'Flaherty, who entered the game with a 7.50 ERA in six relief appearances, had another tough outing and took the loss. He issued a leadoff walk to ex-A's first baseman Chris Carter in the 11th then walked center fielder Colby Rasmus. Catcher Hank Conger advanced the runners with a sacrifice bunt, and left fielder Robbbie Grossman grounded a single to left, giving Houston a 4-2 lead.

Grossman took second on a throwing error by left fielder Mark Canha and scored when right fielder George Springer lined a two-out single to left off left-hander Fernando Abad, making it 5-2

The A's had pulled even with two runs in the bottom of the 10th. Once again they refused to quit. Second baseman Eric Sogard lined a leadoff single to center off right-hander Pat Neshek, and shortstop Marcus Semien followed with a two-run shot to left, cutting Houston's lead to 5-4.

Pinch hitter Ike Davis singled to left, beating the shift, and took second on a wild pitch. But Neshek retired designated hitter Ben Zobrist on a pop fly and first baseman Billy Butler on a fly ball to right.

Left-hander Tony Sipp came on to face center fielder Sam Fuld, who launched a deep fly to right that curved foul, then worked a walk.

Right-hander Chad Qualls retired third baseman Brett Lawrie on a fly ball to deep center field for his first save.

Astros left-hander Dallas Keuchel allowed just two hits over nine shutout innings, singles by center fielder Craig Gentry and Semien, but didn't figure in the decision. He struck out five and walked two while lowering his ERA to 0.62.

A's left-hander Scott Kazmir pitched seven shutout innings and lowered his ERA to 0.99 but got a no-decision. He allowed just five hits -- all singles -- struck out seven and walked three. Kazmir left a scoreless game after throwing 106 pitches.

The Astros scored twice in the top of the 10th inning, taking a 2-0 lead. Oakland right-hander Dan Otero gave up a two-out double to Springer then intentionally walked former A's shortstop Jed Lowrie. That brought designated hitter Marwin Gonzalez to the plate, and he lined an opposite-field, two-run double to the left-center alley.

Oakland answered with two runs in the bottom of the inning off former A's right-hander Luke Gregerson, ending a 19-inning scoreless streak. Fuld grounded a pinch hit single to right with one out. Then with two outs, pinch hitter Stephen Vogt reached safely on an infield single, moving Fuld to second.

Then right fielder Josh Reddick, Oakland's third pinch hitter of the inning, lined a two-run double to left-center. Reddick took third on the throw and tried to score when the ball got past Conger, but Conger threw him out at home by a few steps as Gregerson applied the tag.

Astros second baseman Jose Altuve went 2-for-4 and extended his hitting streak against Oakland to 27 games with a third-inning single off Kazmir. Altuve's streak is the longest in franchise history by an Astro against one team. Former Astro Lance Berkman held the previous mark of 21 games against the Rockies.

NOTES: Astros RHP Josh Fields (right groin strain) was activated from the 15-day disabled list Friday. The reliever had been on a rehabilitation assignment with Triple-A Fresno since April 11. ... Astros INF/OF Jonathan Villar was optioned to Triple-A Fresno, making room on the 25-man roster for Fields. ... A's INF/OF Ben Zobrist made his first start since injuring his left knee on April 19 at Kansas City. Zobrist, who pinch-hit in the ninth inning Thursday against the Angels, started at designated hitter. He said theknee still "doesn't feel super comfortable" but has improved. ... A's