Their cause wasn’t helped by an early red card for Callum McGregor – sent off for picking up a second booking in the move that led to Rangers opening the scoring through Kemar Roofe in the 26th minute.
Celtic recovered from that double whammy to level through Odsonne Edouard on the half hour but a chaotic six minute spell ended with Alfredo Morelos quickly restoring Rangers’ lead, and the hosts never looked back, adding another two goals in the second half through Roofe and substitute Jermain Defoe.
The defeat leaves Celtic a whopping 23 points behind their Glasgow rivals, who are now two games from completing an undefeated league season.
Here’s how the Celtic players rated:
9. James Forrest - 6
Showed flashes of what Celtic have missed but rusty in his final execution. Fluffed a first half chance and delivered one pinpoint cross that Turnbull should have converted. Photo: Craig Foy - SNS Group
10. Odsonne Edouard - 6
Not enough graft and hold-up work after Celtic went down to 10 but came alive in the final third and reacted well to nod home equaliser Photo: Craig Williamson - SNS Group
11. Mohamed Elyounoussi - 7
Celtic's busiest forward player was the one trying to create the spark. Unlucky not to score with terrific strike tipped onto bar by McGregor but fluffed clear chance in second half Photo: Craig Foy - SNS Group
12. Ryan Christie - 5
Put in a few challenges but unable to create anything in last half hour Photo: Craig Williamson - SNS Group