Manchester City launched an investigation after a pitch invasion after the final whistle.
The Villa boss said that the Sweden keeper was attacked.
In a statement, City said Olsen was assaulted and they had launched an immediate investigation.
Manchester City would like to apologize to the goalkeeper of the team who was attacked by fans after the final whistle.
The individual responsible will be banned from the stadium for the rest of their lives after the club launched an immediate investigation.
Thousands of fans poured onto the playing surface after the title was confirmed, but Villa's players were still on the pitch.
The answer is no, when asked if everyone got off the pitch okay.
The goalkeeper was attacked. I think those questions should be directed to Manchester City.
Attacks on players are on the rise after pitch invasions.
Crystal Palace boss Patrick Vieira was involved in an altercation with a supporter of another team after his side lost to Goodison Park.
After their League Two play-off semi-final defeat by Port Vale, the players of Swindon Town were physically and mentally abused.
The other League Two semi-final, played on Wednesday, also ended in a pitch invasion with the Stags boss saying such incidents are getting concerning.
The fan who ran on to the pitch and headbutted Billy Sharp at the end of the game was jailed on Thursday.
Speaking on Sunday, he said he was worried about the safety of players and worried about the recent pitch invasions.
The Frenchman was asked about the altercation at Goodison Park.
There were a lot of invasions in the premier league. I think there is a real issue here.
You don't know what can happen. You fear for the players when you don't know what will happen.
We want to be safe in our workplace.
I don't think the FA is the only one who has to look at what is the best way to stop these things happening anymore.