Further testing on Matt Moore's left elbow Wednesday revealed a tear in the ulnar collateral ligament. The Rays and Moore are deciding on the next step, which is either surgery or rehabilitation.

“Honestly, let's just wait until (today). I don't have everything in,” Rays manager Joe Maddon said after Wednesday's 7-3 loss to the Royals. “It needs to be looked at a little more deeply, because it's not a slam-dunk surgery right now.”

Moore, placed on the disabled list Tuesday with left elbow soreness, could miss at least a month if he chooses to rehab without surgery. If the 24-year-old opts for the reconstructive surgery known as Tommy John surgery, he will miss at least 12 months.

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Moore left Monday's loss to the Royals in the fifth inning complaining of pain in his left elbow when he threw his change-up. He said the pain was similar to, but not as severe as, the pain in the same location he experienced last summer that forced him to the disabled list for more than a month.

An MRI taken Tuesday in Kansas City was inconclusive, so Moore flew Wednesday to Pensacola to visit top orthopedic surgeon James Andrews for another MRI.

This time, contrast dye was injected into the elbow for better results, and those results showed a tear.

“I don't think it's fully torn, from what I understand,” Maddon said.

Moore said Tuesday he was hoping the injury was just bruising from the ligament rubbing against something in his arm while he threw the change-up, because the pain did not occur when he threw his other pitches. He also said he didn't feel a pop, which some pitchers experience when they completely tear the UCL.