"Three-run homers are killers," interim manager Tom Lawless said. "If we make the plays, we have nobody on with two out, and we go from there. That's the importance of being able to play defense, and you've got to play solid defense up here to win ballgames."
Six of the runs the Mariners scored in the inning were unearned thanks to the defensive miscues. Starter Brad Peacock couldn't escape the mess, leaving after 3 1/3 innings. He allowed six hits and seven runs, though only two of the runs were earned.
"Errors happen," Peacock said. "I've still got to make pitches and do my job out there. It's a tough one."
Jose Altuve, making a rare start at designated hitter, shook off Thursday's 0-for-6 performance by going 3-for-3 to extend his Major League lead to 216 hits. In doing so he tied Magglio Ordonez for the most hits in a season by a Venezuelan-born player in Major League history.
"[Ordonez] was one of the best hitters to play from Venezuela, and I'm happy to tie him in hits in a season," Altuve said.
Altuve also set a franchise record with his 24th three-hit game of the season, surpassing the previous record of 23, set by Craig Biggio in 1998.
"I was 0-for-6 last night, and I knew I wasn't going to go 0-for-6 again," he said. "I tried to go out there and swing the bat and saw, like, three or four pitches. I was ready to swing."
Lawless removed Altuve from the blowout game after three at-bats in order to help him win the batting title. Altuve leads the American League with a .343 average with eight games remaining.
"He's got something special going," Lawless said. "To win the batting title is a very impressive thing, and if we do some things like that. ... If the game is 5-4, we won't do that. But to try to protect that for him, I'm going to try every way I can to do that for him."
Altuve doubled and scored on a Dexter Fowler single in the first inning, but Dustin Ackley tied the score with the first of his two homers, a solo shot into the Crawford Boxes in the third.
Mariners starter Taijuan Walker (2-2) walked Robbie Grossman to start the third, and Altuve followed with a hit and steal of second. Walker then walked Carter to load the bases, but he struck out Fowler and Jason Castro swinging and got Matt Dominguez to fly out to end the threat.
"We kind of let them off the hook there," Lawless said. "We had the bases loaded and four, five and six up, and to [Walker's] credit, he made pitches. If we can get a base hit there and another base hit or something, he might be out of the game right there. When you get those opportunities, you've got to take advantage."
The fourth was nothing short of a nightmare for the Astros, as the Mariners sent 12 batters to the plate. Zunino's homer made it 4-1, and Kyle Seager greeted reliever Jake Buchanan with a three-run homer that pushed the lead to seven runs.
Walker held the Astros to two runs on eight hits in 5 2/3 innings and earned his third career win, all of which have come against the Astros. Four of his seven Major League starts have been against Houston.
"I think eight runs helped him quite a bit," Mariners manager Lloyd McClendon said. "But he knows that club, he knows what they're capable of doing. More than anything, he executed pitches very well tonight. I can't tell you how pleased I was with his execution and his command of the strike zone."