Updated

Houston, TX (SportsNetwork.com) - Jason Castro and Marc Krauss hit back-to- back home runs during a four-run sixth and the Houston Astros took down the Oakland Athletics on Monday, 7-3, in the opener of a three-game set.

Castro's two-run blast to right-center against Jesse Chavez broke a 3-3 tie and gave the Astros the lead for good. Krauss followed with a solo shot and following a pitching change, Matt Dominguez hit the third home run of the inning to make it 7-3.

Chris Carter had a three-run homer earlier for the Astros, who snapped a five- game losing skid with the triumph and beat Oakland for just the fourth time this season in 11 meetings.

"It's nice to see guys up and down the lineup getting involved tonight," Castro said. "That's all we can ask for, to keep swinging the bats."

Chavez (8-7) was charged with six runs on five hits in 5 1/3 innings of work, while his counterpart Brett Oberholtzer (3-7) made a little history en route to his first win since May 30. Oberholtzer became the first lefty starter in Houston franchise history to beat Oakland in 36 games.

The 25-year-old lefty allowed three runs on eight hits over 6 2/3 innings.

Oakland struck first, taking a 1-0 lead on Derek Norris' RBI single in the second inning. Stephen Vogt hit a solo homer in the third to make it 2-0.

Chavez didn't allow a hit through two innings and got Robbie Grossman to pop to shortstop to open the third, but consecutive singles put two on for Carter, whose 21st home run of the season had the Astros in front.

The A's briefly tied it on Yoenis Cespedes' sacrifice fly in the visiting fifth, but Houston's home run barrage in the sixth was the difference.

Carter walked with one out to set up Castro's shot, which proved to be the game-winner. After Krauss chased Chavez from the game with his homer to right, Dan Otero came on and served up Dominguez's 13th of the year.

"I thought (Chavez) was throwing the ball really well," said A's manager Bob Melvin. "Real similar to how he did last time out."

Nick Punto and Jed Lowrie drew walks against Tony Sipp in the ninth inning, but Vogt flied to center to end the game.

Game Notes

Prior to the game, the A's placed outfielder Craig Gentry on the 15-day disabled list and selected the contract of outfielder Billy Burns from Double- A Midland. Burns went 0-for-1 in his only at-bat, becoming the first rookie to see the field for the A's this season ... Oakland is 22-8 against Houston since the start of last season ... The A's went 1-for-5 with runners in scoring position.