The Everton fan who appeared to try and strike a Lyon player could land his club a UEFA sanction , while Ashley Williams may face punishment too following the ugly scenes in Thursday's Europa League tie.
Williams instigated a fracas in front of the Howard Kendall Gwladys Street End midway through the second half at Goodison Park when he barged into Lyon goalkeeper Anthony Lopes.
A melee involving players from both sides ensued and moved to the advertising hoardings, where one Toffees fan, who was holding a child with one arm, pushed Lopes in the head before hitting out at him again.
While that was occurring, Williams seemed to raise his hand to Lucas Tousart's face, yet the only initial outcome of the skirmish was a booking for Everton's captain-for-the-night and Lyon's match-winner Bertrand Traore.
Speaking after the Toffees' 2-1 loss, Williams told BT Sport 2 of the scuffle: "It's what happens, it's football. It is what it is.
"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."
Yet retrospective action could be forthcoming from UEFA, for both Williams and the club, a possibility ex-Premier League referee Graham Poll deems likely.
"Ashley Williams and Everton will surely face further sanction from UEFA once video evidence is studied," he said in the Daily Mail.
"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."
It was the referee, Bas Nijhuis, who under-fire Toffees manager Ronald Koeman blamed for his players losing their cool during a defeat which leaves them facing Europa League elimination having taken just one point from three games.
"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. (Nabil) Fekir in the first half dived 10 times.
"I understand with my players, that comes out of frustration."
It compounded another miserable night for Everton and Koeman, who is under mounting pressure with his team having won just two of their previous dozen fixtures.
"I think the performance was under the level in the first half - a lot of mistakes, a lot of doubts, players without any confidence," he said.