As Pettine considers quarterback change, Manziel is ready

Browns coach Mike Pettine could decide to change quarterbacks.  The backup says he’s ready for the assignment. “The door is definitely open for a change at the quarterback position,” Pettine told ESPN’s Sal Paolantonio, via Mary Kay Cabot of the Cleveland Plain Dealer.  “It’s not like we’re just going to go back to Brian.  This…