Moussa Dembele scored twice against Hamilton Academical to give Celtic a 21st straight Premiership victory.
The visitors, sitting bottom of the table, had limited the leaders to a Stuart Armstrong strike against the woodwork until Dembele struck.
The French striker curled home a superb shot on the stroke of half-time.
Dembele scored his second after 59 minutes from the penalty spot after Kieran Tierney was brought down by Massimo Donati.
Celtic’s 15th consecutive win in all competitions means they retain their 24-point lead over Aberdeen, who beat Ross County.
Accies remain one point behind Inverness Caledonian Thistle, who had lifted themselves off the bottom with Friday’s win over Rangers.
Dembele makes difference
Celtic were in command of this game, but that alone was not enough to overcome Hamilton.
The visitors were disciplined, well-organised and spirited, while their hosts lacked the edge and intensity that has distinguished the best of their work this season.
The game became a test of Celtic’s patience until Dembele delivered a moment of improvisation and exquisite technique.
Spinning on the ball then dragging it past Massimo Donati, he made room 25 yards from goal then lifted a shot over Hamilton goalkeeper Gary Woods and into the far corner of the net.
It was striking enough for goalkeeper Craig Gordon to wait for his team-mate at the side of the pitch as the players left at half-time and congratulate him.
Dembele almost added a second early in the second half, but his shot from Tierney’s cross was deflected wide.
The Celtic full-back still managed to create a goal for Dembele, though, being brought down inside the area for a penalty that the French striker converted calmly.
Hamilton suffer familiar tale
Not for the first time this season, much of Hamilton’s play was solid and dependable.
They set up to contain Celtic and their work was diligent and thorough enough to frustrate the home side.
Darian MacKinnon was typically bullish in central midfield, while Danny Redmond kept trying to prompt counter-attacks from deep positions.
Steven Boyd, a graduate of the club’s youth academy, looked promising up front, but mostly Hamilton were trying to maintain their hold on a clean sheet.
Redmond did shoot wide early on and one break upfield ended with MacKinnon playing Dougie Imrie in, but he sliced his shot wide of the goal.
The visitors had a claim for a penalty late on, when Gramoz Kurtaj went down inside the area, but the Hamilton forward was booked for diving instead.
Just before the end, Eamonn Brophy also had a header tipped over by Gordon.
Hamilton were bottom of the table before kick-off and there is no sense of panic at the club, but this was a difficult day for the visitors.