TAMPA – The battle for the third wide receiver spot is fast becoming one of the more intriguing of the offseason for the Tampa Bay Buccaneers, and that battle just got a new combatant. The Bucs on Tuesday signed former University of South Florida wideout Carlton Mitchell. The 6-foot-3, 215-pound Mitchell originally entered the league in 2010 as a sixth-round draft pick (177th overall) of the Cleveland Browns. He has since played in 16 NFL games, all for the Browns between 2010 and 2011. Hampered by a leg injury during training camp in 2012, Mitchell was released by the Browns before the start of the 2012 season. He signed with Jacksonville on Nov. 21 but was released by the Jaguars on Nov. 24.