The two countries will revive hostilities in Polokwane tonight in another Group A Africa Cup of Nations qualifier.
According to Le Roy, Bafana Bafana boss Mashaba made disrespectful comments before heading home on the weekend.
"I've never said anything concerning your coach, but I did not appreciate his remarks after our game. He said our goalkeeper was not very good and that he knows how to beat Congo, because if we don't score in the first 10 minutes we can't do anything," Le Roy is quoted as saying by Times Live.
"That is completely stupid because we did not score first against Nigeria and we did not score in the first half against Sudan. It's very important for people not to say much after the game. Yes, you can talk to the journalists before the game, but you have to keep a lot of humility."
The Frenchman added: "Football is the school of humility. People sent me back the interview [with Mashaba] and I didn't like it."