The match at Udinese's Bluenergy Stadium was suspended for approximately 10 minutes in response to the incident.
Maignan was seen expressing his concerns to referee Fabio Maresca, after which he removed his gloves and left the field, followed by his teammates.
It is understood that the Milan keeper had also informed the referee about alleged monkey chants earlier in the match, leading to an announcement in the stadium urging fans to cease such behaviour.
News of the incident quickly spread, and several teams, players and organisations took to social media in response to the alleged racial abuse.
AC Milan posted on X: «There is absolutely no place in our game for racism: we are appalled. We are with you, Mike.»
Current Serie A leaders Inter Milan promptly responded to the post in support of their city rivals, adding: «We are brothers of the world, against all forms of discrimination. By your side.»
The official account of the Serie A added: «The league condemns all forms of racism.»
Noah Okafor, who scored the winning goal after the match was restarted, told DAZN: «These things have nothing to do with football, and they hurt; there is no such thing as black or white. We are all the same.»
Former Arsenal striker Ian Wright also wrote on X: «Solidarity from the rest of the team. Keep walking off!!! We did 'playing through it' and nothing has changed. Points deductions needed, the fines are pointless.»
Three minutes after the match restarted, Maignan conceded a goal to a Lazar Samardzic shot, and the teams entered the break
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