The Vikings signed rookie quarterback Tyler Thigpen on Friday. Thigpen, a seventh-round pick out of Coastal Carolina, impressed coaches with his arm strength and mobility during a rookie minicamp earlier this month and is the first of Minnesota's eight 2007 draft picks to sign a contract.

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."

The Vikings signed free agent defensive tackle Howard Green, who hasn't played since 2004, on Tuesday. Green started 12 games for the Saints in 2004, registering a career-high 53 tackles. The former sixth-round draft choice by Houston in 2002 was coached by Vikings defensive line coach Karl Dunbar in college at LSU. The Vikings also announced the hiring of Derek Mason as assistant defensive backs coach.