Currently on the disabled list with a left groin strain, Beckett has been diagnosed with irritation of an upper arm nerve that causes numbness in his right hand and fingers. A nerve specialist in Dallas confirmed on Tuesday what the Dodgers had already suspected.
Beckett was back in Los Angeles on Wednesday and feeling optimistic that he will return this season.
"Absolutely. I really do," he said. "We're going to try and beat this thing in the next four weeks, and if it takes a little bit longer but we have progression in those four weeks, we'll wait a little bit longer. You really don't want this to leak into next year either."
Beckett is 0-5 with a 5.19 ERA in eight starts. He was part of a nine-player trade with Boston last August.
"I made five or six starts with this and things weren't going very well," he said. "I wasn't really helping anybody out by going three innings, giving up five runs, the bullpen is dead for three days and (Clayton) Kershaw has to throw 140 pitches his next start. I want to help these guys win and be a part of that."
Beckett said he experienced no pain while he was pitching, but he was ineffective and fell behind in the count.
"You don't have a feel," he said. "You don't have the fine motor skills to throw the ball where you want it. It's just a struggle."
Manager Don Mattingly was more cautious in his assessment of Beckett's possible future contributions.
"If he's out another month, how long is it going to take him to come back from that?" he said. "I know it's going to be a little while before he starts throwing, so I know it's going to be a little while before we know anything."
Beckett said he saw a couple doctors and a physical therapist during his three days in Dallas, and he learned a lot about his condition.
"There are a lot of guys who have had surgery for this and were successful. There were a few guys where it hasn't been successful," he said. "We're going to do everything we can to beat this thing without surgery, and if we have to move that way, that's what we'll do."
The Dodgers and their high-priced payroll have struggled so far this season, falling into last place in the NL West while dealing with a rash of injuries that has affected the starting rotation. Besides Beckett, Chris Capuano, Zack Greinke, Ted Lilly and Chad Billingsley have spent time on the DL.
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