Cotton sharp in 4-inning stint

PEORIA, Ariz. — Three spots remain open in the A’s rotation, and management wouldn’t mind certain pitchers claiming those jobs. Such as Jharel Cotton. “He’s had some success for us,” manager Bob Melvin said. “He’s had a little difficult time being consistent. Yeah, we’d love for him to be in it.”

Cotton took a step in the right direction Wednesday night with four innings of one-run, three-hit ball in the A’s 7-3 Cactus League win over the Mariners. He was particularly effective with his swingand-miss changeup — “my money pitch,” he said — and, in one stretch, struck out five of six batters.

The run came on a fourthinning play in which Cotton was shaken up. A pitch got away from catcher Bruce Maxwell, and Cotton went to cover the plate but slipped and rolled his left ankle on the soft dirt, which Melvin said was “like a sandbox.”

Cotton was slow to get up but convinced Melvin and trainer Nick Paparesta he was OK to stay in the game, then retired two of his final three batters.

“I don’t want to call it quits after giving up a run like that,” Cotton said.

After a promising start to his big-league career late in 2016 (2.15 ERA in five starts), Cotton struggled last season (5.58 ERA in 24 starts), and he said Wednesday, “I’m thankful the A’s let me grind through that.”

A goal in 2018 is to “give my team a chance to win” on a more consistent basis, he said. “Last year, I didn’t do that.”

Said Melvin: “When he’s throwing strikes and getting ahead, he’s striking guys out, making guys look bad. It’s just about the consistency, and hopefully he can put the next one together like he did tonight.”

Cotton threw two scoreless innings in his Cactus League debut, then gave up four runs in his next appearance. Fingers returns: Hall of Fame reliever Rollie Fingers is back in the organization as a special assistant to the president, Dave Kaval.

The A’s will be celebrating their 50th anniversary in Oakland, and Fingers said in a statement, “I can’t believe that it’s been that long since I put on an A’s uniform as a player in 1968. I look forward to working with the club and connecting with our fans.”

Fingers will be at the Coliseum on Opening Day when the A’s honor their 50th anniversary team. John Shea is The San Francisco Chronicle’s national baseball writer. Email: jshea@sfchronicle. com Twitter: @JohnSheaHey