SEATTLE -- The offensive-laden Astros seem to have uncovered a new -- and surprising -- power source, as Cameron Maybin ripped a two-run homer off Mariners closer Edwin Diaz in the ninth inning on Wednesday to lift Houston to its seventh straight win, a 5-3 decision for a Safeco Field sweep.
Maybin, claimed off waivers from the Angels a week ago, came off the bench and sent a 100.2-mph fastball from Diaz off the right-field foul pole for his ninth homer of the year and third in six games for the Astros. He also hit a tiebreaking two-run homer to lift the Astros to a 3-1 victory in Justin Verlander's debut on Tuesday night.
"He's been a nice spark for us on a lot of levels," Astros manager A.J. Hinch said. "He's come in with some energy, he's come in with a ton of enthusiasm. He's a good player. We knew everybody would like him. He's obviously performing at a high level and earning more at-bats. Big swing tonight."

Diaz, who gave up a leadoff double to Carlos Beltran before Maybin's one-out, opposite-field home run, has been one of the American League's better closers, with 31 saves.
"I think I have to tip my hat to Maybin." said Diaz. "He hit a great pitch, great location. He hit it late, and it was a homer. The one to Beltran I thought was a good pitch, too. If I throw that pitch a little higher to Maybin, maybe it's a fly ball. But I thought I threw a perfect pitch, and he hit it pretty good."
The triple-digit fastball was the third-fastest pitch hit for a home run in the Majors this year and the fastest pitch to be hit for a homer against the Mariners since pitch tracking began in 2008.
"Just trying to look for something I can hit the other way, and I did," Maybin said. "Luckily it found the opposite side of the yellow, man. It was a big hit and we needed it. I was fortunate enough to get it."
With their second-longest winning streak of the season, the Astros improved to 86-53 and maintained a three-game lead over the Indians for the best record in the AL after Cleveland won its 14th straight earlier in the night. Houston's magic number to clinch the division is nine.

The three-game sweep dropped Seattle to 69-71, putting a dent in the Mariners' AL Wild Card pursuit, as they've dropped to 3 1/2 games behind the Twins for the final postseason spot with 22 games to go.
Mariners rookie Andrew Moore, a September callup making his first big league start since July 26, held the Astros to three hits and two runs over six innings in his best outing of the season. The Mariners' No. 4 prospect, per MLBPipeline.com, is 1-3 with a 5.89 ERA in eight appearances (seven starts).
• Moore exceeds expectations
Lance McCullers (7-3, 3.97 ERA) came off a five-week stint on the disabled list with a back injury to throw 5 1/3 frames for the Astros. He didn't allow a hit until Kyle Seager's leadoff homer in the fifth, but the Mariners knocked the righty out in the sixth. He finished with four hits and three runs allowed in a 76-pitch outing.
• McCullers makes statement in return from DL

Seager's homer was his 22nd on the season and third in the past three days. He's gone deep in five of his last nine games against the Astros. The long ball snapped McCullers' Major League-best streak of 49 1/3 innings without giving up a homer.
"Disappointing series, no doubt," Mariners manager Scott Servais said. "We were right in every game, we just didn't get big hits late and that's what it takes to beat the good teams. It's timely hitting. I did think our starting pitching was very competitive and kept us right in games. We just didn't get the big hits late."

MOMENTS THAT MATTERED
Reddick to the rescue: McCullers handcuffed the Mariners early, and he got some help in the third when right fielder Josh Reddick moved swiftly on a low-liner off the bat of Ben Gamel to make a nice diving grab. Statcast™ credited Reddick with his first "5-star" catch of the season, the highest rating awarded. According to the metric, there was only a nine percent catch probability, as Reddick had to cover 38 feet in just 2.9 seconds.

Double trouble for Marwin:Marwin Gonzalez, filling in for Jose Altuve at second base for the day, went 2-for-4 for Houston with a two-run double in the fourth off Moore. He also doubled and scored in the seventh on an RBI single by George Springer that tied the game at 3. The Mariners brought in lefty specialist Marc Rzepczynski to turn the switch-hitting Gonzalez to the right side in the seventh, but he doubled anyway. After Rzepczynski issued a one-out walk to Max Stassi, Seattle summoned Nick Vincent, and he struck out pinch-hitter Maybin before giving up the single to Springer on a blooper to center.
"For whatever reason, the seventh inning was our Achilles heel in this series, " Servais said. "Zep has been lights out until the last couple hiccups, and Vincent has been as good as they come. I thought Vinny threw the ball well and tied up Springer for the soft single to center. But you're putting him in that spot where there's no wiggle room. It's a tough spot to put those guys in, but they are our guys. We had the right guys out there, the Astros were just a little better."

QUOTABLE
"That dude's for real that's throwing at the end right there. For that kind of at-bat to be put up in a big situation for us and give us a bigger cushion with a homer is huge." -- McCullers, on Maybin's homer off Diaz
"He did it twice. He's really made some good adjustments over the last couple years in his swing, trying to stay inside some balls, and certainly that's what he did there. Everybody knows Eddie's got a great arm, and the Astros had a good approach against him tonight." -- Servais, on Maybin's game-winning homers

WHAT'S NEXT
Astros: The Astros are off Thursday before opening up a four-game series against the A's in Oakland 9:05 p.m. CT on Friday. Collin McHugh (2-2, 3.25 ERA) will take the mound in the opener. The clubs will play a doubleheader on Saturday.
Mariners: After an off-day Thursday, the Mariners resume their nine-game homestand on Friday with newly acquired lefty Mike Leake (8-12, 4.14 ERA) on the mound in the 7:10 p.m. PT start against Angels right-hander Ricky Nolasco (6-12, 5.08 ERA). Leake won his Mariners debut last week with seven innings of two-run ball against the A's.
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