The 23-year-old complained of discomfort in his right hand following his most recent start Saturday. Later that night, he was taken to a local hospital to check if a blood clot was the reason for the problem. Cobb was then placed on the 15-day disabled list Sunday.
"I'm relieved to know what it is and that it isn't career threatening in any sort of way," Cobb said before Wednesday's game against the Royals. It's also good to know that I am in the hands of a specialist who has been down this road before and can treat it properly. I'm ready to get this part over and get on with [Rays head athletic trainer] Ron [Porterfield's] rehab program."
The surgery will be performed at the Baylor Medical Center in Dallas and the recovery time is expected to be 10-12 weeks.
Once that time passes, Cobb is expected to assume his normal winter throwing routine and be completely recovered by the start of Spring Training.
Before the injury, the rookie posted a 3-2 record and a 3.42 ERA in nine starts for the Rays.
"It's a tough one," manager Joe Maddon said. "But from what I understand, it's not going to be a long-term serious kind of a thing. He's going to be fine. We're just happy that we caught it at this particular moment."