"He has a really good curveball," Rays manager Joe Maddon said.
Cobb said his curveball has been especially good since the end of the 2012 season.
"I started throwing a new curveball last year, and it's starting to really come around right now and at the end of last year," Cobb said. "I think that's more of a consistent feel I'm going to have for it game in and game out the rest of the year hopefully. Throughout Spring Training, it was there for me every game. Hopefully that's a sign of things to come the rest of the season."
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.