FORT LAUDERDALE, Fla. -- Troy Patton's season came to a halt on Tuesday, when he underwent an operation that will correct a problem with his left shoulder but will also keep him off the mound for eight months or more. Patton's injury was classified as a minor tear in his left labrum, which is regarded as one of the most common pitching injuries.

"His rotator cuff was clean," said Baltimore manager Dave Trembley, summarizing the results. "He should be a candidate for a throwing program in the instructional league and should be fine to go in Spring Training [in 2009], so that's a positive."

Patton's case has been followed closely because he was one of the main pieces involved in the Miguel Tejada trade. The Orioles have known about his injury since before they finalized the deal, but they brought Patton to Spring Training in the hope that a restful offseason would heal his shoulder and skirt the need for surgical intervention.

Patton went four months without throwing but was never able to shake his discomfort in the early days of Spring Training. He was held behind many of his peers to refine his stuff in non-game settings, but Patton eventually opted to shut things down and see a doctor. An arthrogram revealed the extent of his injury, and Patton went to Los Angeles for a final opinion.

The final examination and resulting surgery were both done by orthopedic specialist Dr. Lewis Yocum. Patton said earlier in the spring that he hoped to get things cleaned up and return to form by the beginning of next season. Now, he'll have to go through months of rehabilitation and strengthening exercises before he picks up a ball again.

Patton, who has a 27-28 record and a 3.01 ERA in 82 Minor League games, is still just 22 years old.

"It's kind of disappointing to miss the season," he said earlier in the month. "But I'm kind of anxious to get it over with, and hopefully feel better and pitch better next season, have a little bit more velocity than I've been pitching with, and I'm looking forward to feeling good throwing a baseball."