The Hoops scored the only goal of the game right after the hour mark of the game but that strike from Ntcham has come under much scrutiny after the game.
Moments before the goal was scored, Rangers midfielder Ryan Jack was fouled but the referee Willie Collum chose to ignore it and let the game flow.
And seconds after this, Celtic FC landed the one and only blow of the game.
After the match, Steven Gerrard had revealed that even the fourth official knew the challenge on Ryan Jack was a foul and conveyed it duly to the on-field referee via the microphone.
But Willie Collum chose to ignore the input and went ahead with his own decision.
Gerrard had said: “For me, it is a foul and it is also a foul for the fourth official. He is shouting down his microphone, ‘foul, foul, foul.’
And now the person who was involved in the tackle – Ryan Jack has revealed what the referee had told him after the midfielder confronted him after the tackle.
“I said, ‘Willie, I thought that was a foul’, but you get nothing back. It’s ‘Go away, get out my face’, whatever,” Jack said in the Scottish Sun.
“There’s nothing you can say. If you do try to approach to ask why it’s a booking and another rash decision that’s going to be made on the pitch.
“It’s frustrating for players that you can’t actually approach a referee and ask for an explanation.
“I feel like I can’t approach him but that goes for most referees nowadays. You can’t approach them, you can’t speak or they’ll book you.”
Rangers fans have been going around claiming that this one mistake cost them the game but the reality is that their team were leagues behind Celtic during the match.
While Celtic were playing their normal game, the Light Blues chose to sit back deep and thump long balls forward towards their strikers, Kyle Lafferty and Alfredo Morelos.
Read: The Old Firm clubs have now even outdone some top Premier League clubs but this time the fans are fuming.