Romelu Lukaku clashed with Inter Milan teammate Marcelo Brozovic at the end of their draw with Champions League opponents Slavia Prague.
The pair exchanged words on the pitch when Brozovic complained to Lukaku about a position he'd taken. The Belgian responded with angry tones.
Gazzetta dello Sport says Brozovic felt Lukaku was insulting him personally and confronted him after the game in the players' tunnel.
Tension quickly spilled over, with the pair having to be pulled apart by teammates.
The match finished 1-1.