Adrian Peterson has been cleared for takeoff. The Vikings first-round draft pick will not need surgery to repair a collarbone that was broken twice last season, an injury that may have caused him to slip to the seventh pick in April's draft. The Vikings said Wednesday that the injury was healing fine on its own and they will not have to insert a protective plate to prevent further injury, a procedure that would have kept the former Oklahoma running back out of action for three to six months. The team said Peterson will be ready for contact drills when training camp opens. "We felt the fracture was well on its way," team physician Dr. Joel Boyd said. "We thought it would be best to let it heal in a natural way."