SEATTLE -- Seattle Mariners starter Taijuan Walker walked off the mound after six solid innings with a bang, having struck out the side while throwing 102 pitches for the game. It was quite a cap off his night.

Except he wasn't finished yet.

Walker came back out and struck out the side again in seventh, then the Mariners held on for dear life to beat the Houston Astros 3-2 on Monday night.

Walker matched a career high with 11 strikeouts on a night when third baseman Kyle Seager recorded his 100th career home run and closer Steve Cishek added his 100th save following a shaky ninth inning.

Seager and Leonys Martin each homered for the second game in a row to lead the Mariners to a 3-1 lead before the Seattle bullpen almost gave it away. Houston shortstop Carlos Correa's RBI single in the eighth cut the deficit to 3-2, then Cishek had to rely on a caught stealing and a game-ending groundout off the bat of Houston's Jose Altuve to get the save.

"I never thought I'd be saying I have 100 saves," Cishek said after the tense ninth inning. "It's really a blessing. I'll celebrate it tonight but forget about it real soon."

The Astros (6-14) stranded eight runners on base, including runners at the corners in the ninth.

"We had plenty of opportunities and couldn't cash in enough runs," manager A.J. Hinch said after his team's sixth loss in seven games.

Seattle's Walker allowed one run off six hits over seven innings while throwing a career-high 118 pitches. Walker (2-0) got better as the game went on, recording six of his 11 strikeouts over the final two innings. His final pitch struck out catcher Erik Kratz to end the seventh.

"I was just fired up, especially those last two innings," Walker said. "I felt better as the game went on."

Houston starter Doug Fister (1-3) needed 113 pitches to get through six innings, issuing a career-high seven walks while giving up a pair of solo homers and three earned runs overall.

"He continued to battle," Hinch said. "He kept the hit total down (to four). They had a lot of baserunners, but all in all he kept us in the game."

Martin's home run tied the game at 1-1 in the third and Seager's 100th career home run broke the tie an inning later. Robinson Cano gave the Mariners a 3-1 lead with an RBI single in the fifth.

Seattle (10-9) moved over .500 for the first time since the season-opening series and won for only the second time in seven home games this year. The Astros fell to 2-8 in road games.

Houston got an RBI single from center fielder Carlos Gomez to open the scoring in the top of the second, then the Astros cut the deficit to 3-2 on Correa's RBI single in the eighth.

Cishek pitched in and out of trouble in the ninth to earn his fifth save of the season. Cishek gave up a walk and two singles but stranded runners on the corners when he got Altuve to ground out to short to end the game.

"I was just trying to throw everything I could at him," Cishek said of the Altuve at-bat. "I was throwing it as hard as I could, and wherever it went, I just hoped he hit a ground ball at somebody.

Gomez got a one-out single in the ninth but was thrown out trying to steal second base.

"It's the story of the last couple weeks, where we beat ourselves a little bit in a close game," Hinch said. "Those (mistakes) are continuing to hurt us."

Houston left fielder Colby Rasmus, who was named the American League player of the week earlier in the day, went 0-for-4 with two strikeouts in the loss.

NOTES: LF Colby Rasmus was named the American League player of the week. It marked the second time in his career Rasmus earned the honor. It also marked the first time in the award's 42-year history that three teammates were honored in each of the first three weeks of the season, as Rasmus joined 1B Tyler White and 2B Jose Altuve as recipients. ... Seattle placed RHP Joaquin Benoit on the 15-day disabled list with inflammation in his right shoulder. Benoit's most recent appearance was Friday and he has a 3.60 ERA over five appearances this season. He has served as the Mariners' setup man but took a few days off earlier this month because of a tired arm. ... Seattle called up RHP Mayckol Guaipe from Triple-A Tacoma before Monday's game. Guaipe was 0-3 with a 5.40 ERA over 21 games during four stints with Seattle last season.