Framber Valdez recorded his fourth consecutive quality start to claim a riveting pitcher’s duel and lead the Houston Astros to a 2-1 victory over the visiting Seattle Mariners on Saturday.

Valdez (4-4) allowed one run on four hits and four walks with five strikeouts over six innings. He has surrendered six total runs over his last four starts and 28 innings. Houston won all four contests.

Valdez retired the Mariners in order only twice, doing so in the first and fifth innings. But he struck out three batters in the third to negate a two-out walk to Julio Rodriguez and induced inning-ending grounders in the second and fourth to strand two baserunners in both frames.

Mitch Garver produced a run-scoring groundout in the second to plate Randy Arozarena, whose leadoff triple helped the Mariners slice a two-run deficit in half. Houston relievers Bennett Sousa, Bryan Abreu and Josh Hader preserved that lead. Hader notched his 13th save.

The Astros struck early against Seattle right-hander Bryan Woo (5-2) and did so by capitalizing on the Mariners’ shaky defense.

Woo surrendered three singles in the bottom of the first inning, but his throwing error following an infield single by Christian Walker enabled Jose Altuve to score the first run from first base. Walker advanced to second on the error and scored when Victor Caraniti followed with a grounder that Seattle second baseman Leo Rivas misplayed into the second error of the frame.

Woo mitigated damage by stranding two runners, setting the tone for the rest of his outing. He struck out Jeremy Pena and Isaac Paredes to strand Mauricio Dubon in the second, retired three batters in succession after Altuve and Walker singled to open the third, and stranded Dubon and Pena on the corners by getting Altuve to ground back to the mound in the fourth.

Jake Meyers hit into an inning-ending double play in the fifth, and Woo erased a leadoff single by Cam Smith by getting Zach Dezenzo to roll into a double play in the sixth. Woo allowed a season-high nine hits over six innings. However, he did not walk a batter and recorded five strikeouts while surrendering two unearned runs. It marked the third outing this season that Woo did not surrender an earned run. Woo has worked at least six innings in all 10 starts this season.

The Astros finished 0-for-8 with runners in scoring position.