With 12 minutes left to play, Rangers substitute Jason Holt felled Patrick Roberts in the box and Ntcham drilled the ensuing spot-kick into the bottom-left corner to put the gloss on a result that never looked in doubt from the moment Celtic took the lead.
It was an uphill battle from thereon for Rangers, they had a man sent off early in the second half and Celtic proceeded to score another two goals.
Rangers man Ross McCrorie was dismissed in the 51st minute, which essentially killed off all hope for them.
The "Outback Ozil" scored against Rangers in a thrilling Old Firm that Celtic won 3-2 at Ibrox just one month ago.
"I asked them to get into a shape and a structure in order to go and press".
"In the second half, we gave them the penalty and sending off which makes their job far, far easier". I don't think we got close enough to them.
Rodgers, meanwhile, said: "I think what the players have done over the past couple of seasons has inspired the supporters into believing the impossible".
"We have to put a performance worthy of their support". We didn't do enough to make them want to stay in the stadium today'.
"We were just passive".
"Everyone will tell you it's one game at a time but we are well aware now that there is a possibility for that and we are going to give it everything we have between now and the end of the season to get that".
'It seems to be the case at times that we've had really good opportunities to claw something back from the game and we haven't managed to do it. "I completely understand his frustration".
"The players need to respond for themselves. That's what we aim to do in every game and we did that easily today". "I will speak to him in the week, we will have a chat and move forward from there".
"There was anger, frustration, all the sorts of emotion you would expect from a changing room that has just gone through that", he said.