SEATTLE -- Houston manager A.J. Hinch knows his pitching staff can throw good fastballs. However, it is the change-of-direction pitches that bring a smile to his face.
Reddick's tiebreaking home run in the fourth inning put the Astros ahead 2-1, and Yuli Gurriel added an RBI single in the sixth for a two-run lead.
Valdez, called up from Triple-A Fresno earlier in the Tuesday, gave the ballclub a lift with his four-plus innings of one-run ball in relief of Brad Peacock. Valdez (1-0) came on at the end of the second inning with two on and two out, and threw two consecutive curve balls to Dee Gordon for strikes, eventually getting out of the jam.
"We threw him into the fire," Hinch said. "He was incredibly impressive. . He pounded the strike zone with a lot of confidence."
Seattle pulled to 3-2 in the eighth inning on Ben Gamel's RBI single to right field, but stranded the tying run at third base after pinch hitter Nelson Cruz and Gordon struck out against the Roberto Osuna to end the inning.
Hector Rondon earned his 14th save with a spotless ninth inning as Houston snapped a five-game skid against Seattle, and remained tied with Oakland atop the AL West standings.
After that, he retired eight of the next nine Seattle hitters.
"With each pitch, and each inning, I felt more and more comfortable," Valdez said.
Both teams used Tuesday as a "bullpen" day. Reliever Nick Vincent made his first career start, tossing two scoreless innings.
Reddick lifted Detwiler's 86 mph changeup deep into the right-field bleachers in the fourth to put the Astros ahead. But the Mariners stayed close behind six double plays, which was a franchise record.
"If you'd have told me that we were in a 3-2 game late with guys on base and the right guys up, we'll take our chances," Mariners manager Scott Servais said. "We didn't get the big hit tonight."
OSUNA `GOING TO FINISH' GAMES
Even though he did not pitch the ninth inning Tuesday, Osuna is expected to see plenty of save chances down the stretch.
"Rondon is going to be used a little more liberally in the seventh and eighth (innings)," Hinch said. "Osuna would be used in the ninth a little bit more."
FELIX MIGHT KEEP NEW ROUTINE
Veteran right-hander Felix Hernandez said he will always think of himself as a starting pitcher, no matter how poorly he performs. But he said he might keep the throwing program he adhered to during his quick stay in Seattle's bullpen.
And Servais said he is not opposed to it, especially after watching the up-and-down Hernandez (8-11, 5.64 ERA) give the team six capable innings in a no-decision against the Astros on Monday.
"For the bullpen guys, they are out there playing catch, and always on flat ground every day working on mechanical things," Servais said. "That is probably a good thing for Felix. Sometimes when you throw more, you get a better feel for the mechanics and where they are at."
Astros: To make room for Valdez, lLHP Cionel Perez was sent to Fresno. ... As expected, 2B Jose Altuve (right knee soreness) was activated from the 10-day disabled list Tuesday. To make room, OF Kyle Tucker was sent to Fresno.
Mariners: With Detwiler coming up, reliever Chasen Bradford was sent to Triple-A Tacoma. In order to add Detwiler to the 40-man roster, INF Zach Vincej was designated for assignment. ... C Chris Herrmann's bruised knee felt better Monday, allowing him to start in place of Mike Zunino. ...
Mariners: Before the game, RHP Hisashi Iwakuma (shoulder) threw 20 pitches at "70-80 percent" velocity to Japanese countryman Ichiro Suzuki, who hit a few sharp line drives into the gap. "It gives me a great idea of where I am right now," Iwakuma said through a team interpreter. ... Ace LHP James Paxton (forearm) could throw a light bullpen session during the day off Thursday.
Astros: RHP Charlie Morton (12-3, 2.85 ERA) has lost his past two games, but has won both of his starts at Safeco Field this season.
Mariners: LHP Marco Gonzales (12-8, 3.91) finishes off the homestand while making his second start of the season against the Astros.
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