AC Milan boss Gennaro Gattuso ushered his row with Tiemoue Bakayoko behind closed doors after being abused by the midfielder amid a sideline bust-up at San Siro.
Bakayoko appeared to swear in Gattuso's direction after raising his coach's ire with the sluggish pace of his preparation to replace the injured Lucas Biglia in the first half of Monday's 2-1 victory over Bologna.
Gattuso eventually decided against introducing the 24-year-old, opting instead for Jose Mauri, and a pointed exchange took place as the game continued in the background.
The latest indiscretion seems set to be the death knell for Bakayoko's career at the club as a turbulent season-long loan from Premier League side Chelsea comes to a close.
His relationship with Rossoneri great Gattuso was already at a low ebb after arriving late to a training session in the lead-up to what eventually proved a crucial win for Milan's top-four hopes.
"I told Bakayoko to warm up, but it took him eight minutes to get ready," Gattuso said of the mid-match incident in a post-game interview with Sky Sport Italia.
"Anybody can insult me, but we'll meet afterwards and look eye to eye.
"I want to speak to him in the change room and in my language, which I can't do on TV.
"The priority right now isn't my ego nor the players'. We wear a glorious shirt and have to do the right things.
"At the end of the year we will give report cards, like in school, and we will see who has behaved well and who has behaved badly."
Milan needed three points to close back to within touching distance of fourth-placed Atalanta and secured the result courtesy of goals from Suso and Fabio Borini.
Mattia Destro reduced the deficit in the second half and the hosts were made to survive the final 15 minutes with 10 men after a frustrated Lucas Paqueta slapped the match official's arm.
It was the second red card in as many matches for Milan, who lost captain Alessio Romagnoli during last weekend's defeat to Torino.
"He's young. He was fouled, put his hands on the referee, I don't think he realised what he was doing," Gattuso said of Paqueta's sending off.
"[The ill-discipline] annoys me and we have to improve in this aspect."