|Everton manager Ronald Koeman confronts the officials|
Several players from both teams clashed in the 64th minute when Everton captain Ashley Williams appeared to shove Lyon goalkeeper Anthony Lopes into the advertising hoardings after the latter had collected the ball from a corner.
An Everton supporter also appeared to push Lopes’ head as the scuffle escalated near the Gwladys Street End stand and the Merseyside club are likely to face disciplinary action by UEFA after the incident.
“I think the irritation grows in the game for our players and in my opinion that was the problem by the referee,” Koeman said after the match.
“The referee was Dutch but he didn’t do anything against the theatre of some of the Lyon players. (Lyon captain Nabil) 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.”
Defender Williams, who scored Everton’s equaliser in the 69th minute, and Lyon striker Bertrand Traore, who scored the winner, received yellow cards.
The loss increases scrutiny of Koeman, whose side sit bottom of their group with no wins in three Europa League games and on a two-game winless streak in the Premier League, where they are 16th in the standings.
Everton host top four contenders Arsenal in the league on Sunday.