HOUSTON (Interstat) — J.P. Crawford hit a grand slam and Cal Raleigh slugged his major league-leading 58th home run in a seven-run second inning, powering the Seattle Mariners to a 7-3 victory over the Houston Astros on Sunday night at Daikin Park.

The win completed a three-game sweep for the Mariners, who extended their lead in the American League West to three games over the Astros with six games remaining in the regular season. Seattle, which has won four straight and 14 of its last 15, improved to 87-69. Houston dropped to 84-72.

Seattle’s offensive explosion in the second inning proved decisive. The Mariners sent 11 batters to the plate, collecting six of their eight total hits in the frame.

The inning began with three consecutive singles by Josh Naylor, Jorge Polanco and Eugenio Suárez to load the bases with no outs. After Dominic Canzone grounded into a force out at home, Victor Robles drew a bases-loaded walk to force in the game’s first run.

Crawford then delivered the crushing blow, launching a 2-1 pitch from Astros starter Jason Alexander over the right-field wall for a grand slam, his 12th home run of the season, to give Seattle a 5-0 lead.

Randy Arozarena followed with a single, and Raleigh then connected on a two-run shot, a line drive to right field for his historic 58th homer, to cap the scoring at seven runs.

That was more than enough support for Mariners starter Logan Gilbert (6-6), who earned the win. The right-hander delivered six strong innings, allowing one run on three hits. He struck out four and walked one. The only damage against him was a solo home run by Houston’s Zach Cole leading off the bottom of the third inning.

Alexander (4-2) was charged with the loss for Houston. He was pulled after Crawford’s grand slam, having been tagged for five runs on five hits in just 1 1/3 innings.

The Astros bullpen, led by AJ Blubaugh’s three hitless innings of relief, shut down the Mariners’ offense for the remainder of the game, but the early deficit was too large to overcome.

Houston chipped away with single runs in the seventh and eighth innings. In the seventh, Cole and Mauricio Dubón singled before Jose Altuve drove in Cole with a line-drive single to right field. In the eighth, Isaac Paredes hit a solo home run, his 20th of the year, to left-center field.

Mariners reliever Carlos Vargas surrendered the run in the seventh, and Matt Brash pitched a perfect ninth inning to seal the victory.

The game-time temperature was 78 degrees, and the contest was played in front of a sold-out crowd of 41,893. The time of game was 2 hours, 50 minutes.

With the victory, Seattle secured the season series against Houston, 8-5. The Mariners, seeking their first AL West title since 2001, also hold a two-game advantage over the Detroit Tigers for the American League’s second playoff seed.

Seattle returns home to begin a six-game homestand to close the regular season, starting with a three-game series against the Colorado Rockies on Tuesday. Houston, now three games back in the division and clinging to a wild-card spot, heads to for a three-game set against the Athletics beginning Tuesday.