Watch: Aston Villa goalkeeper Robin Olsen assaulted during Man City pitch invasion

Pep Guardiola condemned the Manchester City fans who assaulted Aston Villa's Robin Olsen up to three times as another Premier League match descended into pitch invasion violence.

The goalkeeper appeared to have been struck a total up to five times - two of them accidental - as delirious Manchester City title celebrations quickly escalated out of control.

Guardiola backed punishments and said "we are so sorry" after Olsen was led away with his head in his hands, having been hit in the back of the head, shoved and taunted, as seeen in footage below.

Roy Keane, the Sky Sports pundit, also expressed fears of an eventual stabbing after "disgraceful" on-field confrontations were also seen involving Everton, Port Vale and Nottingham Forest fans over the past week.

Despite extra police on hand at the Etihad, the mass pitch invasion quickly overwhelmed security, with City supporters also climbing on the goals and breaking a crossbar. Olsen escaped injury but appeared initially hurt in video footage of him being hit in the head, struck a second time and then being shoved in the back by another fan.

"I’m so sorry," said Guardiola later as he reflected on the Olsen incident and other clashes between players and fans in recent days. "I’m so sorry on behalf of the club to Olsen and Aston Villa. I don’t think there were intentions but the emotions of people there. It’s always difficult to understand why the people respond in that way and cannot celebrate themselves to do these kind of things. Hopefully we can discover who the person was and he’ll be punished. I don’t know how [to stop it] - you cannot put 1,000 guards to control all the people there. We are so sorry. It’s the bad news of today."

An unidentified City player was also inadvertently clattered into by a fan who came racing over and collided with him as he slid along the turf. After Steven Gerrard said during his post-match press conference that "my goalkeeper was attacked", City promptly issued an apology, promising a "indefinite stadium ban" for offenders involved.

On Sky, Keane and Gary Neville attacked the actions of fans. “It’s disgraceful," said Keane. "A player or a manager is going to be seriously injured. If you’re mad enough to come on and punch a player, then you’re going to be mad enough to stab a player. There’ll be something crazy happen. I think when Covid happened, people came back from Covid and forgot how to behave themselves. Idiots, scumbags, disgrace.”

Neville added: “What’s happening? This brilliant last 30 years where we’ve brought the fences down in English football and the fans 99 times out of 100 have respected the fact that you don’t run on the pitch because they enjoy the family environment. We’ve obviously got far more children coming to the game, far more women coming to the game, and all of sudden these last few weeks and months we’ve got these idiots running on the pitch."

Kevin De Bruyne was mobbed before being immediately surrounded by stewards and police who battled through the crowd to get him to safety. Fans, including school-age boys and girls, also climbed on the goals, causing one of the crossbars to collapse.

Security officials delivered a tannoy message requesting fans to clear the pitch and a warning sign was displayed on the giant screens. However, coming in the same week that Crystal Palace manager Patrick Vieira was involved in a confrontation with an Everton fan, the Premier League is facing intense pressure this summer to clampdown on a surge in fan disorder.

Vieira, speaking for the first time about the incident after Palace's 1-0 final day victory against Manchester United, called for both the league and the Football Association to take stronger action.

The former France World Cup winner had been unaccompanied by staff or security when he retaliated to abuse from an Everton fan in midweek. "You don't know what can happen," he said. "When you don't know what can happen of course you fear for anything, for the players. We want to be safe and the best way to do that is we need to reflect on what is the best way for those kind of things not to happen on the field. 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."

The latest scenes at Manchester City are likely to attract the interest of the Football Association. City apologised to Olsen and said the club "has launched an immediate investigation and once identified, the individual responsible will be issued with an indefinite stadium ban".