Bryce Miller pitched six quality innings as the Seattle Mariners defeated the visiting Houston Astros 3-2 on Monday night in the opener of a four-game series between American League West rivals.

The division-leading Mariners scored three runs in the first inning off Framber Valdez (3-3) and made the early lead hold up.

Miller (4-5) opened the game with four hitless innings and ended up allowing two runs on five hits. The right-hander walked two and struck out six.

Trent Thornton, Gabe Speier and Andres Munoz each pitched a scoreless inning of relief, with Munoz striking out two in the ninth to earn his 11th save of the season.

Seattle struck right out of the gate, as J.P. Crawford led off the bottom of the first with a double down the right field line. Crawford advanced to third on Julio Rodriguez's one-out single to right, and Mitch Garver walked to load the bases.

Cal Raleigh hit a fly ball to right-center and Jake Meyers made a diving catch on the warning track before crashing into the wall, with Crawford scoring on the sacrifice fly. Ty France then grounded a run-scoring single to left and Mitch Haniger did the same to center to make it 3-0.

The Astros didn't have a hit until they strung together three in a row to get on the scoreboard in the fifth.

Meyers lined a one-out single to left, Jon Singleton singled to right and Jose Abreu, in his first game back after being optioned to the team's spring training complex in West Palm Beach, Fla., on May 1 to work on his swing, lined an RBI single to right-center.

Victor Caratini followed with a sacrifice fly to right to pull Houston within 3-2.

Valdez settled down after the first to record a quality start. In six innings, he gave up three runs on six hits, with three walks and four strikeouts.