Merseyside Police have launched an investigation after crowd trouble at Goodison Park - during which a fan appeared to attack a player.
Everton's Europa League tie with Lyon was marred with violence after Ashley Williams barged into the French team's goalkeeper.
During the ensuing scuffle, involving several players, an Everton fan carrying a child appeared to hit Anthony Lopes in the face.
The fracas occurred midway through the second half. Everton had been 0-1 down at the time and went on to lose 1-2.
Police in Merseyside have confirmed they are looking into the incident.
Everton were quick to announce they intended to ban the fan for life.
A statement from Merseyside Police released on Friday morning read: "Merseyside Police can confirm officers are investigating following a disturbance on the pitch during a football match between Everton and Lyon at Goodison Park last night, Thursday 19th October.
"Detectives will be reviewing footage and speaking to witnesses to establish what, if any, offences have been committed."
The coming-together happened in front of the Howard Kendall Gwladys Street End after defender Williams pushed Lopes into the hoarding.
As a number of players attempted to pull the two apart, a fan carrying a young boy dashed up to Lopes and hit him in the face - sparking protestation from the travelling team.
Speaking after the match, Williams told BT Sport 2 of the scuffle: ''It's what happens, it's football. It is what it is."
Anyone with information "which could assist the investigation" is asked to contact the force on 0151 777 4065 or Crimestoppers anonymously on 0800 555 111.