SEATTLE -- After delivering the game-ending throw, Houston Astros center fielder Carlos Gomez lay on his back and took a few seconds to soak in the celebration that broke out around him.

The Astros didn't clinch any kind of playoff berth Wednesday night, but at least they regained control of their own destiny.

"Every game is a playoff game," said Gomez, who played a full game for the first time since Sept. 12 while battling a sore back. "Every little thing counts. We play a game and have to play until the game's over."

Colby Rasmus delivered a go-ahead RBI single in the seventh inning, Houston overcame four errors, and Gomez finished off a 7-6 win over the Seattle Mariners with a double play from center field as the Astros stayed in the thick of the postseason hunt.

Houston (84-75) kept alive its slim hopes of winning the American League West title while moving past the Los Angeles Angels in the AL wild-card standings. The Astros are a half-game ahead of Los Angeles, which opens a four-game series with Texas on Thursday while Houston takes its final day off.

The Rangers (86-72) hold a 2 1/2-game lead over the Astros in the division, three games over the Angels (83-75).

"We put a lot of pressure on the teams ahead of us, and we put pressure on the teams chasing us, too," Houston manager A.J. Hinch said. "I love the way this team responded."

The Astros rallied from a three-run deficit, which first baseman Chris Carter made up with one swing of the bat. Carter's three-run homer in the sixth tied the score 6-6 before Rasmus delivered the go-ahead single an inning later.

Astros designated hitter Evan Gattis hit a fly ball toward Seattle left fielder Brad Miller with one out in the seventh, and Miller misplayed the ball by taking a step forward as it went over his head. Gattis ran all the way to third before Rasmus singled off Danny Farquhar (1-7) to give the Astros a 7-6 lead.

Reliever Tony Sipp (3-4) earned the win after throwing 1 1/3 scoreless innings, while closer Luke Gregerson worked a shutout ninth to notch his 31st save of the season.

"I didn't doubt our character coming into this series, and I don't doubt it now," Hinch said.

The Mariners (75-84) had runners on base in the eighth and ninth innings but couldn't deliver the big hit. Houston finished off the win when Gomez turned a double play on a flyout, throwing to first to double up pinch runner James Jones.

"It was just a bad read," Seattle manager Lloyd McClendon said of Jones getting caught too far off first. "One thing I won't do is make excuses for players. He should have got back."

Gomez credited right fielder George Springer with calling out to him to throw to first, then he delivered a strike that barely caught Jones to end the game. As the Astros broke into celebration, Gomez was on his back in center.

"It was an unbelievable throw," Gomez said. "All I could think was: 'Yes!'"

Now the Astros have a day off Thursday before beginning a three-game series at Arizona.

"We just need to take care of business," said starting pitcher Scott Kazmir, who got roughed up for six runs (four earned) on seven hits over 4 1/3 innings. "We know what we need to do. We need to go out there, get these last three wins and go from there."

Second baseman Robinson Cano had four hits for the Mariners, while catcher Jesus Sucre added a career-high three hits.

Houston third baseman Luis Valbuena hit a solo homer, while Astros second baseman Jose Altuve and shortstop Carlos Correa also drove in runs.

Back-to-back home runs from third baseman Kyle Seager and designated hitter Nelson Cruz in the bottom of the fifth inning put the Mariners in front 6-3. Seager's three-run homer on the first pitch he saw was his 26th of the season, establishing a career high. Three pitches later, Cruz took Kazmir deep for a solo home run, his 44th of the season.

The Mariners had five consecutive hits in the fifth, ending Kazmir's outing.

Valbuena sparked a three-run top of the fifth inning with a leadoff home run as the Astros took a 3-2 lead. Altuve and Correa added RBIs in the frame.

Seattle used eight pitchers. Starter Tony Zych, a reliever who was making his first major league start, allowed three hits over 2 2/3 scoreless innings while throwing 39 pitches. After original starter James Paxton was scratched earlier in the week due to a torn fingernail, the Mariners went into Wednesday's game with a pitch-by-committee plan. Mayckol Guiape and Logan Kensing, Seattle's first two relievers out of the bullpen, gave up five hits and a walk in the three-run fifth.

The Astros overcame four errors, three wild pitches and two unearned runs allowed to get the win. Gomez's game-ending double play might not have been the most appropriate way to finish off an error-filled game, but the Astros were happy to get out of Seattle with a series win.

"It wasn't pretty," Hinch said, "but at this point I don't care what it looks like. A win's a win."

NOTES: Houston CF Carlos Gomez was in the starting lineup for the first time in 2 1/2 weeks Wednesday. Gomez's last start came on Sept. 12, as a back injury limited him to just two games as a late-inning replacement. ... The Mariners announced that they are shutting RHP Felix Hernandez down for the rest of the season. Hernandez (18-9) originally was scheduled to start Friday's game against Oakland, but the organization decided not to add any more innings to his 29-year-old arm. ... Houston announced LHP Dallas Keuchel will start Friday's opener of the final series in Arizona. Keuchel (19-8) is seeking his first 20-win season. He will move one spot up in the rotation to stay on his usual four days of rest, with RHP Collin McHugh moving back to Saturday.