HOUSTON — John Buck called the progress: “baby steps.” Manager Lloyd McClendon described it as a learning experience. But for Brandon Maurer, it was a hurdle that needed to be overcome as a starting pitcher.

Maurer picked up his first win of the season, pitching five innings, giving up four runs on six hits with two walks and three strikeouts in Seattle’s 8-7 win at Minute Maid Park on Sunday.

It wasn’t the prettiest of outings. But all involved believe Maurer made some progress in meeting his enormous potential as a big-league pitcher.

“It was a battle, but I saw something in the kid that I liked today,” McClendon said. “I saw some fortitude, some guts.”

Like so many starts, there were times when Maurer looked dominant and others where he struggled, particularly with runners on base.

The seminal moment came in the fifth inning. His teammates had given him a 7-3 lead and it looked as though he was squandering it.

Maurer gave up a leadoff homer to Jonathan Villar to start the inning. He then walked Jose Altuve and gave up a single to Dexter Fowler. After getting Jason Castro to fly out, a passed ball moved both runners into scoring position. The game was speeding up on him. In past times, that is where he would fall apart.

McClendon had Wilhelmsen warming up in the bullpen and ready, but stuck with Maurer.

“It’s tough,” McClendon said. “You’ve got a lot of things weighing on you. It’s not easy as a manager to make that decision whether or not you pull him. What does that do for his ego, his belief in what he can accomplish? But you’re also weighing what’s good for the team, your responsibility to the team to try and win the game. Believe me, it was not easy. It was a gut-wrenching inning.”

The 23-year-old right-hander rewarded McClendon by striking out Matt Dominguez and getting Alex Presley, who had homered and doubled off him earlier, to fly out to end the threat.

It earned the respect of his manager.

“He went at it when he didn’t have much left and he fought through that fifth inning,” McClendon said. “That’s a real tough position to be in. Short bullpen where a guy as one of your starters has an opportunity to win. You want to believe in him, you want to give him an opportunity. He came through.”

McClendon’s faith in him gave Maurer some confidence.

“It felt good that he left me in there and let me get out of it,” he said.

The Mariners made an expected roster move after the game, informing outfielder Abraham Almonte that he’d been optioned to Class AAA Tacoma. The Mariners didn’t announce a corresponding move, but it appears that outfielder James Jones will be called up from the Rainiers and join the team in Oakland. Jones was not in the lineup Sunday for Tacoma.

“I need to just go down there and feel like how I used to feel at the plate, and I think everything will be fine,” Almonte said.

Ryan Divish: 206-464-2373 or rdivish@seattletimes.com. On Twitter: @RyanDivish