Swindon manager Paolo Di Canio insists that unless goalkeeper Wes Foderingham apologises he is 'out'.
Foderingham was substituted after only 21 minutes of their 4-1 defeat at Preston, with the game at 2-0.
Foderingham was replaced by 18-year-old Leigh Bedwell but reacted angrily to being hauled off, and Di Canio insists he must apologise.
"There is nothing wrong with changing a goalkeeper, we are not talking about [Petr] Cech, we are talking about Wes, before he met us he had not played first-team football," Di Canio told Sky Sports.
"If he was not happy, we were fuming - it is obvious that if he does not say sorry to everybody then he is out, he is out - and we have to believe him, he has to convince us."
Di Canio insisted that Foderingham deserved to be taken off.
"He was one of the worst players I have ever seen," said Di Canio.
"He's another player like the others, why can't we change the goalkeeper? Because the goalkeeper has a different coloured shirt?
"I know Wes, he was the worst player against Stoke in the cup - he was far away the worst player, he made a rubbish performance. But I covered for him because we won 4-3. But what he did was not only the mistake, which can happen to anyone, but the arrogance when he started moaning to the other players - that was the worst thing for me.
"A player that doesn't recognise his mistakes which were clear from miles away, he started moaning to his team-mates. Out there he behaved as the worst professional, arrogant, ignorant athlete I have ever seen. And if he doesn't come out and apologise to the fans, to the professionals in general, he is out from my team."