Foderingham was at fault for Swindon's first goal in their 4-1 defeat, and after he was withdrawn by Di Canio, Foderingham kicked a water bottle and stormed off the pitch.
When asked why he substituted Foderingham, Di Canio told the Swindon Advertiser: "Because he was one of the worst players I have ever seen in a football match.
"The arrogance later, when he started moaning to the others, that was the worst thing for me because it let me realise that a player doesn't recognise his mistakes that was clear miles away.
"Today he started behaving as the worst professional; arrogant, ignorant in some way — not as a person, as an athlete — I have ever seen.
"If he doesn't come out and say sorry to the fans, for the professionalism in general, he is out from my team."
Swindon's defeat meant that they slipped down to eighth in the League One table.