Celtic survived a stoppage-time scare as they came from behind to beat St Johnstone 3-1 in the Scottish Premiership on Sunday while Rangers returned to winning ways.
In the early kick-off, Brendan Rodgers' men trailed to Diallang Jaiyesimi's first goal for St Johnstone at half-time after failing to deal with an in-swinging corner.
But Callum McGregor netted with a powerful strike in the 67th minute and Matt O'Riley hit his seventh Premiership goal of the season 12 minutes later when he finished brilliantly from 22 yards.
The final outcome hinged on two incidents in time added on.
Saints substitute Jay Turner-Cooke headed off the post from close range before Celtic broke seconds later and Tomoki Iwata squared for fellow sub James Forrest to guide the ball home.
Rodgers said he was furious with his team after a sub-par performance in the first half.
"I think that's the angriest I've ever been as a manager at half-time," he told Sky Sports. "At this club the standards are very high. Our levels need to be much better.
"It's a reminder that teams in this league can hurt you when you drop off.
"You must have that intensity from the first whistle, but the reaction in the second half was really good."
Brighton loanee Abdallah Sima scored twice for Rangers in a 2-0 win against St Mirren at Ibrox as Philippe Clement's side stayed eight points behind Celtic with a game in hand.
Rangers had drawn their previous two matches, against Aberdeen and Aris Limassol, but Sima quelled growing frustration in the stands when he broke the deadlock for the unimpressive home side with a strike just before the break.
Rangers grew stronger in the second half and Sima grabbed a second in the 70th minute with a fine finish to take his tally for the season to 11.
Hibernian beat Aberdeen 2-0 in Sunday's other game.
