Lazio boss Delio Rossi admits he rowed with defender Guglielmo Stendardo.
There were reports of a locker room bust-up between the two men this week and Stendardo is not included in the squad for Wednesday's Coppa Italia encounter with Napoli.
"Professionals must put themselves at the disposal of the team. There is nothing on the contract about guaranteeing a starting place," warned Rossi.
"If someone is a constant fixture in the side it is because they earned it on the pitch. I make the decisions, he did not agree."
This boosts reports that Stendardo is set for a January transfer away from the Olimpico.
"Whoever thinks he is too big for Lazio would do well to tell the club, there's no problem. I want to underline though that Stendardo has not been frozen out. He simply has not been called up for this game and he trained today."