Arsenal manager Unai Emery says Granit Xhaka was "wrong" to react angrily and gesture to the fans as he was substituted during his side's Premier League draw with Crystal Palace.
The Gunners captain was booed as he walked off the pitch at Emirates Stadium, prompting him to cup his ear.
He then took off his shirt, walked past Emery and stormed down the tunnel.
"He's wrong but we are going to speak inside about that situation," Emery told BBC Match of the Day.
The Arsenal boss added: "I want to be calm but, really, he was wrong in this action."
News of the change was first greeted with ironic cheers but they quickly turned to boos as Xhaka took his time to leave the field, sparking an angry reaction from the 27-year-old.
It is not the first time Xhaka has been booed by his own fans this season, with Emery publicly defending the Switzerland international after a game against Aston Villa last month.
That uneasy relationship with the Gunners fans did not stop Emery appointing Xhaka as club captain in September after the summer departure of Laurent Koscielny.