Manchester City have apologised to Robin Olsen and vowed to indefinitely ban the fan who attacked Aston Villa's goalkeeper during a pitch invasion at the Etihad.
Villa boss Steven Gerrard, when asked if everyone got off the pitch OK, said: "The answer is no.
"My goalkeeper was attacked. I think those questions should go to Pep [Guadiola] and Manchester City."
City swiftly released a statement.
"Manchester City would like to sincerely apologise to Aston Villa goalkeeper Robin Olsen, who was assaulted after the final whistle at today's match when fans entered the pitch," the club said.
"The club has launched an immediate investigation and once identified, the individual responsible will be issued with an indefinite stadium ban."
The assault, which came as fans celebrated City's dramatic title win on Sunday, is the latest in a series of incidents following mass incursions onto the pitch.
Last week a Nottingham Forest fan was jailed for 24 weeks after headbutting Sheffield United's Billy Sharp following a promotion playoff match.
Crystal Palace manager Patrick Vieira was involved in an altercation after Everton fans invaded the pitch on Thursday at Goodison Park.
Further footage has since emerged of Palace players Wilfried Zaha and Ebere Eze being confronted by fans. The Football Association and Merseyside Police are investigating.
"There are real issues here to reflect on," said Vieira on Sunday.
"You don't know what can happen. When you don't know what can happen of course you fear for anything, for the players.
"As a coach, manager, player or staff we want to be safe in our workplace. I think there is a big issue on the FA and Premier League's plate to deal with."
Vieira revealed he would be happy to speak to the FA about his own incident but stressed England faced a country-wide problem.
Australian Associated Press
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