HOUSTON -- Houston entered Friday night with losses in nine of its last 11 games and in need of a momentum shift.
Gurriel hit a game-ending home run in the 10th inning after Reddick's tying shot in the eighth, and the Astros beat the Seattle Mariners 2-1.
"We've had a couple tough games here and to win, gives us a lot of confidence moving forward," Gurriel said through a translator.
Gurriel hit a 2-2 pitch from Matt Festa (0-2) off the facade in left field for his eighth homer. The home run was Gurriel's first career game-ending homer and second career game-ending hit.
"I didn't feel great my previous at-bats, but in that at-bat, I remained focused, locked in," Gurriel said. "I hit a foul ball. I knew I could hit a fastball, and then I got the next one. Hit it out."
Gurriel was hitless in four at-bats prior to the home run.
"Yuli who had not had a good night at all -- he popped up to the infield every time -- fouls a couple balls off and gets a fastball he can handle and we walk off winners," Houston manager AJ Hinch said. "Really an emotional win for us in a game where it felt like we were in so many positions to win and we needed the win."
Reddick hit a solo home run to right in the eighth to tie it at 1. That snapped a streak of 17 scoreless innings for the Astros.
"It felt like one of our biggest hits in the last week and a half," Reddick said. "That's the swing we've been waiting on to pick up not only ourselves, the team, the ballpark. It was a completely different atmosphere when I came across the plate and saw our dugout going crazy. It felt good. Luckily, I hit it."
Austin Nola put the Mariners ahead 1-0 in the third with his first career home run.
"I thought I needed to go a little bit more to the left to make it into the little grandstand there," Nola said. "A little bit farther out. So, I didn't know. I just looked and I said it's not on the ground so it must be out."
Will Harris (2-1) pitched around a single in the tenth for the win.
Houston missed a chance to get on the board in the seventh, with Myles Straw forced to hold at third after he missed the base on a single by Jake Marisnick. After Austin Adams walked George Springer to load the bases with one out, Adams got Jose Altuve to ground to third, with Tim Beckham nailing Straw at the plate. Adams struck out Alex Bregman to end the inning.
"You come in here you know you have to score more than one run to beat this club," Seattle manager Scott Servais said. "We just weren't able to do it offensively tonight. Our pitching continues to throw the ball really well, just didn't do a whole lot against their pitching."
Houston starter Wade Miley yielded one run and three hits in six innings.
"We've been grinding," Miley said. "It's been tough for everybody as a team. That's what good teams do: pull together and find a way to win. We outlasted them tonight. We were able to pick up a big win late."
Astros: RHP Brad Peacock was placed on the 10-day injured list with right shoulder discomfort. Hinch said the Astros expect to have Peacock back in the rotation after the All-Star break. ... Houston recalled LHP Reymin Guduan from Triple-A Round Rock to take Peacock's spot on the roster. ... 1B Yordan Alvarez was out of the lineup Friday with a sore left knee after leaving Thursday's game in the third inning. ... RHP Joe Smith threw one scoreless inning in a rehabilitation assignment at Round Rock on Friday night.
Mariners: LHP Yusei Kikuchi (4-5, 5.11 ERA) starts Saturday looking to build off his last start Sunday in which he allowed three runs over six innings in a win over the Orioles. The left-hander has allowed six runs or more in three of his last six starts.
Astros: RHP Justin Verlander (10-3, 2.67) looks to continue his solid season Saturday after earning the win in his last start Sunday, striking out nine and yielding three runs in seven innings against the Yankees.
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