Tom Brady's four-game suspension for his role in using under-inflated footballs during the AFC championship game last season has been upheld by NFL Commissioner Roger Goodell.
Brady, one of the National Football League's most popular players and in many ways the face of the sport, could take the case to federal court in a bid to overturn to the suspension.
The New England Patriots' star quarterback was suspended by NFL executive Troy Vincent in May following a league-sanctioned investigation by Ted Wells. The Patriots were fined $1m and docked a pair of draft picks.
NFL-hired investigator Ted Wills determined, in a 243-page report, that Brady was complicit in a plan to deflate the footballs below league standards, a move that can make the ball easier to grip.
Attorneys for Brady, 37, a four-time Super Bowl champion, had previously indicated that if the quarterback is suspended at all they would take the case to federal court.
The Patriots beat the Indianapolis Colts 45-7 in January's AFC title game, a game played in raw conditions in which the ball might have been difficult for a quarterback to grip.
Brady has denied any knowledge of a plan to deflate the footballs, a program Wells said was carried out by two Patriots employees, officials' locker room attendant Jim McNally and equipment assistant John Jastremski.