FORT MYERS, Fla. — Early in camp, right-handed reliever Luis Guerrero looked like a strong candidate to make the Red Sox’ Opening Day roster.

The 24-year-old was in the high 90s with his fastball and allowed one hit and one walk while striking out six in 3 scoreless innings (three relief outings) to begin Grapefruit League play. That came after dominating for Boston last September.

But control soon became an issue and the Red Sox optioned him to Triple-A Worcester on Wednesday. He walked eight batters and gave up six runs in his final four Grapefruit League outings (2 ⅔ innings).

“ Erratic,” manager Alex Cora said. “He didn’t throw too many strikes. He walked a lot of guys. He was behind in the count. We’ve got to get him going. I think it started in Bradenton. He was all over the place and he knows it. The good thing about him is he didn’t get upset. He’s like, ‘I got to keep working. I got to keep working. I’ll be back.‘”

He didn’t allow an earned run in 10 innings over nine appearances for Boston in his first big league stint. Control had been issue for him throughout the minors. But he cut down on the walks during the second half with Worcester last year and finally made it to the big leagues.

Cora pointed out that young players can let their nerves get to them when they are trying to make the big league team out of spring training camp for the first time.

“That comes into play, too,” Cora said. “Sometimes they try to do too much. And our job as an organization is kind of like ‘Slow it down. You will be fine.’ It’s going to take more than 26 guys to play good baseball throughout the season and then get to where we want to go. But the timing’s not right now. He’ll go down there. Get him to attack the strike zone again. I think he stopped using the fastball more lately. He started mixing up his secondary pitches and he wasn’t able to throw too many strikes.”

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