Daniel Vogelbach clubbed a pinch-hit grand slam in the eighth inning, and the Seattle Mariners extended their winning streak at Minute Maid Park to five games with a 4-1 victory over the host Houston Astros on Monday.

Vogelbach was the third of three consecutive pinch hitters to face Astros right-hander Hector Rondon (2-5), who recorded the first two outs in the eighth courtesy of two splendid diving catches from center fielder Jake Marisnick.

But after getting ahead in the count 1-2 against Denard Span, Rondon fired three successive fastballs out of the zone to load the bases.

Vogelbach then got a 1-1 fastball at the top of the strike zone and crushed it 398 feet into the home bullpen in right-center field. Vogelbach's exit velocity of 105.3 mph on his fourth home run of the season was the third batted ball of 100-plus mph allowed by Rondon in the frame, following Nelson Cruz (100.6) and Ryon Healy (104.8).

Rondon surrendered four runs on four hits and a walk in the eighth. He is 0-3 with a 10.50 ERA over seven appearances this month.

The Astros survived a shaky start from rookie left-hander Framber Valdez, whose control issues didn't prevent him from working five scoreless innings while departing with a one-run lead.

Valdez stranded two baserunners in the first inning by fanning Cruz, Healy and Kyle Seager in succession, and he induced inning-ending double plays in the third and fourth to erase one-out walks.

Valdez walked two batters in the fifth inning but escaped on a Jean Segura groundout.

Valdez allowed just two hits and recorded six strikeouts. He also walked five batters and uncorked a wild pitch while throwing 81 pitches, 41 for strikes.

Mariners left-hander Wade LeBlanc held Houston hitless through three innings but allowed consecutive two-out doubles to Yuli Gurriel and Marwin Gonzalez in the fourth to give the Astros a 1-0 lead.

LeBlanc allowed one run on three hits and three walks with five strikeouts over 5 1/3 innings. Mariners closer Edwin Diaz recorded his 56th save for winner Ryan Cook (2-1).

The Astros had their lead over the idle Oakland Athletics in the American League West cut to four games.

--Field Level Media