Toffees skipper Ashley Williams' push on goalkeeper Anthony Lopes ignited a heated confrontation between several Everton and Lyon players which continued off the pitch and in front of the Howard Kendall Gwladys Street End.

While players continued to push each other in front of the fans, one Everton supporter, who was holding a child, appeared to push Lopes' head and seemed to aim a punch in the direction of the keeper and defender Mouctar Diakhaby.

The Lyon players noticed that and shouted in his direction before things eventually cooled down.

Referee Rob van de Ven produced a yellow card for Williams and Lyon striker Bertrand Traore, with the former fortunate to perhaps escape further punishment having raised his hand in Lucas Tousart's face.

Williams went on to head in an equaliser for Everton soon after but Traore's winner consigned the Toffees to a 2-1 defeat.

The Wales international played down the incident after the game.

"It's what happens, it's football. It is what it is," Williams told BT Sport 2.

"It's high emotions. We want to win the game, they want to win the game and stuff happens. That was just one of those times."

Former Premier League referee Graham Poll is certain Williams and Everton will not have heard the last of the incident.

Writing for the Daily Mail, he said: "Ashley Williams and Everton will surely face further sanction from UEFA once video evidence is studied.

"Williams totally lost the plot.

"There were numerous players from both teams involved in the melee behind the Lyon goal and even a fan from the Everton section at the Gwladys Street end became involved - first pushing then appearing to aim a punch at a Lyon player.

"The fact that a couple of Everton backroom staff had to enter the field to calm Williams down showed how out of control the captain was and, while their intervention helped, they should not enter the field of play.

"The UEFA delegate and referee's observer will have met with the official after the game and discussed their findings before submitting individual reports. Unless the referee ill-advisedly says he saw everything, sanctions really must follow.''

The loss to Lyon left Everton with just one point from their three Europa League ties this year and heaped further pressure on Koeman.

The Toffees boss claimed his players' hot heads were caused by referee Rob van de Ven's officiating.

"I think the irritation grows in the game for our players and in my opinion that was the problem by the referee," Koeman argued.

"The referee was Dutch but he didn't do anything against the theatre of some of the Lyon players. Fekir in the first half dived 10 times.

"I understand with my players, that comes out of frustration. I don't know what happened but I can understand it."

Lyon boss Bruno Genesio had no complaints about how the fracas was handled.

"I think everyone did their job in that situation," he said. "We could then get on with the game and thinking about football, which was the main thing."

Koeman made five changes to his starting line-up, leaving out a number of experienced players, and it was youngster Mason Holgate who naively slid in on Marcal to concede a penalty.

For the remainder of the first half, Koeman accepted his players looked bereft of confidence.

"[It was] really stupid," he said of Holgate giving away the spot-kick.

"I think the performance was under the level in the first half, a lot of mistakes, a lot of doubts, players without any confidence."