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07/14/11 10:42 PM ET

Anderson undergoes Tommy John surgery

OAKLAND -- Following a disappointing first half, not even the All-Star break could pass smoothly for the A's, who on Thursday announced that left-hander Brett Anderson underwent season-ending Tommy John surgery.

The successful reconstructive procedure to the ulnar collateral ligament in Anderson's left elbow was performed by Dr. James Andrews in Pensacola, Fla., on Thursday morning. The operation involved the removal of the gracilis tendon in Anderson's hamstring, which was transplanted to the elbow and used as a graft on top of the ligament.

The A's pitcher was in the midst of his third trip to the disabled list in the past two years -- each time because of elbow discomfort -- and initially believed Tommy John surgery to be imminent following the injury in early June. Andrews, though, opted to give him a platelet-rich plasma injection, as he did last year, but there was not enough improvement to avoid surgery.

"We gave it the time off and rehabbed it, but when we went back out and started throwing again [on July 4], it really didn't just feel much better," A's head trainer Nick Paparesta said. "It felt about the same as it did previously.

"It came to a point where they realized the conservative approach and the rehab, it's failing. Dr. Andrews said, 'Hey listen, it's on you a little bit more, this hasn't worked, what do you want to try to do next?' And he said, 'I want to definitely have the surgery done.'"

The 23-year-old Anderson is facing a recovery time of at least a year, though up to two years is not uncommon, meaning a return to the mound might not come until 2013. That would mark the final season of a four-year, $12.5 million deal -- which includes club options for '14 and '15 -- he signed before last season. He was 3-6 with a 4.00 ERA before the injury and is 21-23 with a 3.66 ERA in his career.

"Hopefully he's in a position where's he going to be just as good, if not better -- which we've seen from a lot of pitchers coming out of this thing, as long as they rehab right," A's manager Bob Melvin said. "A lot of times, the strength and velocity can go up.

"It's something that needed to be done. We explored all the different options to potentially avoid having it done, which you can certainly understand, because you don't want surgery unless you absolutely have to. But this is one surgery guys have come back from very well, so we expect that to be the case with him."

Fellow A's hurler Joey Devine needed nearly two full years to return to his old form following Tommy John surgery, while lefty Josh Outman was out for almost the same amount of time. Oakland pitchers Andrew Bailey and Grant Balfour have also undergone the operation.

"I think you want to give yourself that buffer zone," Paparesta said. "I think with Devine and Outman and the outcome they've had, if you just say 12 months, you're probably putting yourself at a little bit of a risk using those type of words. You're looking at about 12-18 with getting back into the same caliber of activity you were doing before."

The hurler's youth, though, is an encouraging factor that could ease the progression. At the same time, rushing the process can only hurt it, and the A's are going to take full advantage of the lengthy recovery period to not only aid Anderson's elbow back to health but take a holistic approach with his body.

"It's the time to get himself in the best shape possible," Paparesta said. "We're not just looking at rehabbing his elbow and making that better. We're looking at making his core stronger, his lower half stronger, maybe get some of his baby fat off him, get him in better cardiovascular shape, having his shoulder get in better shape, so that when he comes back it's quicker and easier.

"If you try to shorten that rehab period, you may get that short period of time when you first get back, but then at the back end of that is when you start paying for it at the end of the road."

Anderson is the second A's starter to endure season-ending surgery. Left-hander Dallas Braden had a torn capsule in his left shoulder repaired in May. Moreover, the injury bug circulating around the club's staff already hit righties Brandon McCarthy and Tyson Ross, the latter who has yet to return.

However, a positive has been found in Oakland's pitching depth. Guillermo Moscoso has been a pleasant surprise for the A's, going 3-4 with a 2.16 ERA in 10 games, eight of them starts. The A's also have options in Outman and Graham Godfrey.

"You play the cards that you have," Melvin said. "You know that injuries are going to be part of the game, and this team has had quite a few. And when a guy like Brett goes down at this point in the season, certainly you feel bad for him, but as a team you just have to move forward and we do have some pitching depth here."

Oakland, which entered the break 12 games behind division-leading Texas and 14 below the .500 mark as a result of not only the aforementioned injuries but more so because of an underachieving offense, is set to begin the second half of the season on Friday against the visiting Angels.

"We have to play more consistent baseball and find ways to score more runs," Melvin said. "The guys know it, and we feel like we have the people here to do it. Hopefully we can string a few games together offensively that we can build on. Success breeds confidence, and that's what we're looking for in the second half."

Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. This story was not subject to the approval of Major League Baseball or its clubs.