OAKLAND, Calif. -- Designated hitter Evan Gattis hit a two-run double in the ninth inning, and the Houston Astros rallied for a 7-6 victory Sunday and their first series sweep of the Oakland A's in franchise history.

The Astros trailed 6-5 entering the ninth inning, but center fielder Jake Marisnick lined a leadoff single off A's closer Tyler Clippard, igniting a two-run rally.

With Marisnick running, second baseman Jose Altuve hit a ground ball to third baseman Brett Lawrie. Lawrie threw to second, but the speedy Marisnick easily beat his throw. The runners then pulled off a double steal.

After right fielder George Springer struck out, Clippard walked shortstop Jed Lowrie intentionally, loading the bases.

Gattis then lined a two-run double over the head of center fielder Sam Fuld, who appeared to break in then stumble as he ran back. Gattis went 2-for-5 and drove in four runs.

Marisnick went 2-for-4 with a two-run homer and scored three times, returning to the lineup after missing two games with a sore leg. Altuve went 2-for-5 and extended his hitting streak against Oakland to 29 games, the longest ever by an Astro against any team.

Houston right-hander Luke Gregerson pitched a perfect ninth inning for his fourth save.

Lawrie drove in three runs for the A's, who lost their fourth consecutive game.

Oakland left-hander Drew Pomeranz lasted only five innings and got a no-decision. He gave up five runs (three earned) on six hits.

Astros rookie right-hander Asher Wojciechowski gave up five runs on five hits over four innings.

The A's grabbed a 2-0 lead in the second inning as first baseman Ike Davis walked, right fielder Josh Reddick tripled and Lawrie hit a sacrifice fly.

The Astros answered with three runs in the top of the third. Leading off, Marisnick reached safely on an error by Davis and stole second. Altuve drilled a line drive off of Pomeranz's left hip for a single, moving Marisnick to third, then stole second.

Gattis drilled a two-run single with one out. Gattis moved to second on a wild pitch and scored on left fielder Colby Rasmus' single to right field.

The Astros added two runs in the fourth on Marisnick's two-run homer to left with catcher Jason Castro aboard after a walk, making it 5-2.

A's manager Bob Melvin wasn't around to see Marisnick's blast. He was thrown out of the game by plate umpire Quinn Wolcott following a heated argument during Castro's at-bat. With a 2-2 count, Pomeranz threw a pitch that Melvin apparently thought caught the outside corner but was called a ball. Melvin got his point across but was ejected.

Oakland pulled even with three runs in the bottom of the fourth. Catcher Stephen Vogt walked and moved to third on Davis' double. Lawrie lined a two-run single to center, moved to third on second baseman Eric Sogard's single and scored on left fielder Craig Gentry's single.

NOTES: A's rookie RHP Kendall Graveman, who struggled in three of his first four career starts, was optioned to Triple-A Nashville. ... The A's recalled RHP Ryan Cook from Nashville to replace Graveman on the 25-man roster and bolster their bullpen. RHP Jesse Chavez will replace Graveman in the rotation. ... Astros OF Jake Marisnick (right leg soreness) returned to the starting lineup after missing two games. ... Oakland RHP Jesse Hahn, who missed his scheduled start Thursday because of a blister on his right middle finger, threw a bullpen session Sunday and said he expects to return to the rotation Wednesday against the Angels. The A's, however, have yet to announce their starter for Wednesday.