Crystal Palace manager Patrick Vieira was involved in an argument with a fan following their Premier League defeat at Everton. Police and the Football Association are investigating the incident.
At full-time, television video showed him being harassed by an Everton fan as fans rushed onto the pitch.
Before being escorted away by other fans, the Frenchman appeared to kick out at the fan.
According to police, no formal report about the incident has been filed.
“An confrontation on the pitch at Goodison Park following the Everton – Crystal Palace match on Thursday is being investigated by Merseyside Police,” the force said in a statement.
“We’re collaborating with Everton to collect all available CCTV footage and interviewing with witnesses.
“There has been no formal complaint lodged, and investigations into the matter are ongoing.”
Everton pulled off a spectacular comeback to win and keep their Premier League position.
When asked about the incident during his post-match news conference, Vieira said, “I have nothing to say about that.”
Frank Lampard, Everton manager, said: “Patrick Vieira is in my thoughts. At the end, I didn’t recognize him. ‘Come in with us,’ I would have urged, though he might not have wanted it.
“Of course, he went 80 yards across the pitch, which is difficult.”
Lampard commented on the pitch invasion: “The fans’ joy was palpable as they walked onto the pitch after surviving relegation.
“If done well, they should be able to stay on the field and have their moment. No problem as long as they behave.”
Dion Dublin, a former England striker, stated on Sky Sports: “We understand how ecstatic Everton supporters are, but you can’t be doing that. You can’t push managers and players around, touching them and screaming in their faces.
“We know it was only one or two people who ruined it for the rest of us. Having spectators on the field is not the way to go. We must stop allowing or allowing fans to enter the pitch. It’s far too risky.”
Following a number of high-profile instances, Vieira’s encounter at Goodison Park has raised worries about pitch invasions in English football.
Following Port Vale’s League Two semi-final shootout win on Thursday, footage on social media appeared to show Swindon players in a brawl with Vale fans.
After his midfielder Jordan Bowery seemed to be assaulted by a spectator late in their win at Northampton, Mansfield manager Nigel Clough said similar events are “becoming alarming.”
A fan was sentenced to prison earlier on Thursday after storming onto a pitch and headbutting Sheffield United captain Billy Sharp following the Blades’ Championship play-off semi-final shootout loss to Nottingham Forest on Tuesday.