Manchester City have promised to issue a lifetime ban to the fan who assaulted Aston Villa's Robin Olsen.
Thousands of home supporters invaded the Etihad Stadium pitch after City sealed the Premier League title yesterday.
Olsen, who had deputised for Emiliano Martinez, was struck by a fan during a pitch invasion.
The shameful attack follows fans at Nottingham Forest, Port Vale and Everton being investigated after flashpoints with players and coaching staff during pitch invasions over the past week.
Villa said in a statement later that Olsen took a 'bang on the back of the head' but is 'completely fine'.