Red Sox prospect Ryan Westmoreland had surgery to repair a torn labrum in his right shoulder yesterday and will be out for four to six months before he can return to game action. Red Sox team physician Dr. Thomas Gill, who performed the procedure in Boston, told Westmoreland’s father, Ron, that everything went well. Westmoreland was at home last night resting comfortably, according to his father.

“It’s very positive,” said Ron Westmoreland. “We’re just glad it’s fixed.”

While Gill was performing the surgery, he also found a few minor issues in the shoulder and “tightened it up.”

Boston selected the Portsmouth native with its fifth-round pick (172nd overall) in last June’s draft. The outfielder had been playing instructional ball in the Dominican Republic until the decision was made for him to have surgery.

“It was a minor procedure to go in there and clean it up,” said Red Sox director of amateur scouting Jason McLeod. “It will slow him a little bit, as far as spring training goes. He won’t be able to play in games during the spring, but we think we have identified the problem. Now, he just has to rehab and work it out. Hopefully, he’ll come back strong and be ready for next summer.”

After the Red Sox signed Westmoreland to a five-year deal for $2 million last August, he was scheduled to participate in the instructional league for the Gulf Coast League Red Sox. But he was shut down because of shoulder issues.

He began rehab and was sent to the Dominican instructional league with six other Sox draftees. He went 10-for-15, with two triples, a double and a home run, in four games.

“He was phenomenal,” McLeod said. “He swung the bat exceptionally well . . . This is bittersweet for us because you get so excited when you hear the reports coming back. Everyone was excited what he was doing offensively, but obviously we want to get him back at full strength. Our goal is to make sure he’s healthy first.”

Unfortunately, Westmoreland’s shoulder was still bothering him, so the Red Sox thought it best to shut him down. He returned to Boston, where he underwent strength tests last Friday. Gill’s recommendation was to have surgery.

Westmoreland is scheduled to begin his rehab on Monday. He should be able to swing a bat prior to the four-month mark and begin throwing soon after. He will spend next month in Fort Myers, Fla.

After the Red Sox drafted him, Westmoreland played in the Bay State Games and, according to McLeod, had a “fantastic” summer.

“It really seemed like Ryan took off,” said McLeod. “Everything just clicked over the summer.”

Westmoreland finally inked a deal with the Red Sox on Aug. 16. The Red Sox’ organization thinks highly of the 6-foot-2, 185-pounder, on and off the field.

“He’s been a lot of fun to watch,” said McLeod. “He’s the All-American kid. He’s a tremendous athlete and a very good student. He’s so well mannered and so well spoken. He’s a kid we are very excited about.”

jmcdonal@projo.com