SEATTLE — Lance McCullers felt really good about his first game back off the disabled list — although it took him a while to get used to it.

The Astros right-hander pitched into the sixth inning, Josh Reddick homered and Brian McCann added a three-run double to lift Houston to a 5-2 victory over the Seattle Mariners on Saturday night.

McCullers (7-1), who had been sidelined with lower back discomfort, allowed one run on four hits in five-plus innings. He struck out eight and walked none in his first start since June 8.

"You just feel really, really fresh, so that's something to get used to," McCullers said. "But, I got out there and just trusted Mac (catcher McCann), and tried to think about my mechanics more than how my arm was feeling. And, it's a positive thing that my arm was feeling good."

Reddick staked the Astros to a 2-0 lead in the third with his eighth home run. George Springer singled to open and Reddick drove a 1-0 pitch from Sam Gaviglio (3-2) over the wall in centre.

"I didn't think it had enough to get out, honesty," Reddick said. "I was just trying to get George over to get Altuve a chance to drive him in. I got a fastball over the middle, didn't really try to pull it too much, tried to get to where I could drive it and fortunately it went out."

McCann's seventh-inning double increased the lead to 5-1.

Seattle, which had won six straight, scored one in the ninth off Ken Giles on a double and three consecutive walks, but Carlos Ruiz struck out looking with the bases loaded.

The Mariners pulled to 2-1 in the sixth. Ruiz doubled to open and took third on Jean Segura's single, chasing McCullers. Ruiz scored on Robinson Cano's single through the right side, but Will Harris got Nelson Cruz to hit into an inning-ending double play.

In the seventh, Springer singled with one out and Reddick reached on catcher's interference. Carlos Correa's two-out single loaded the bases. McCann followed with a drive to right that Mitch Haniger briefly had in his glove on the diving attempt as he raced toward the line, but the ball popped free as he hit the ground.

"It just came out last minute - unfortunate," Haniger said. "I thought I had a shot. I knew it was going to be close, but I didn't know if I was going to have to dive or not. I was just unable to bring it in."

Gaviglio allowed two runs on six hits in six innings, but the Astros had runners in scoring position in each of the first five innings. He struck out three and walked three.

McCullers retired the first 12 hitters, striking out six, before Cruz beat out a single on his slow roller to third to open the fifth inning. Kyle Seager doubled to centre, with Cruz holding at third, but McCullers worked out of trouble.

He struck out Haniger, Cruz was caught in a rundown on Jarrod Dyson's fielder's choice grounder to second, and Taylor Motter struck out.

"It was nice to see him come out pretty hot," Astros manager A.J. Hinch said. "He was mid-90s from the very beginning, had a really good breaking ball. Cruised through his first few innings, never really got into any trouble. They put a couple good swings on him mid-game, but I don't think we could have asked for much more coming back from a long break."

Reddick made a pair of sensational diving catches in left, robbing Segura to open the first inning, and preventing a run in seventh with his inning-ending grab of Motter's sinking liner with a runner on second.

TRAINER'S ROOM

Astros: 1B Marwin Gonzalez was a late scratch from the starting lineup due to right oblique tightness and was replaced by Yuli Gurriel. "They came to me after batting practice and said he had a little bit of soreness in his side, oblique area, so it was a pretty decision to scratch him," Hinch said. "We'll know more tomorrow, but it was easy to not play him tonight."

ASTROS MOVES

After McCullers was activated from the 10-day DL, RHP Joe Musgrove, who allowed nine earned runs in 3 1/3 innings in Friday's 13-3 loss at Seattle, was optioned to Triple A Fresno. ... RHP Jordan Jankowski was recalled from Fresno. RHP Brad Peacock, originally scheduled to start Sunday, was placed on the paternity list.

UP NEXT

Astros: Rookie RHP Francis Martes (2-0, 5.02 ERA) starts the series finale at Safeco Field on four days' rest in place of Peacock. Martes has allowed four earned runs in 10 2/3 innings in his two starts.

Mariners: LHP Ariel Miranda (6-3, 4.04 ERA) makes his third start of the season against the Astros. Miranda has a 2.20 ERA in seven starts at Safeco Field, compared with 6.56 on the road.