Brendan Rodgers praised Celtic's "persistence and quality" after two late goals at St Johnstone took them six points clear of Rangers at the top of the Scottish Premiership.
It looked like Saints might hold out for a draw in Sunday's clash but winger James Forrest broke the deadlock in the 78th minute before Timothy Weah, on for injured fellow substitute Odsonne Edouard, clinched the win a minute from time.
Hoops defender Kristoffer Ajer was sent off in the closing moments by referee Willie Collum for preventing Saints substitute Callum Hendry making his way towards the Celtic goal.
But Rodgers, whose side had also beaten St Johnstone 2-0 at Parkhead on Wednesday night, declared himself very satisfied with another victory, saying: "It was a good demonstration of our persistence and quality in the game.
"It was a very good performance against a team that are so difficult to play against. We had everything thrown at us today in terms of injuries and whatnot.
"The game went how we thought it would go, similar to Wednesday night where we had to be patient while playing with the intensity. We had really good tempo in our game.
"We created chances and kept a clean sheet, which is really important."
Rodgers - already without Kieran Tierney, Dedryck Boyata, Leigh Griffiths, Tom Rogic, Olivier Ntcham, Tony Ralston and Filip Benkovic for various reasons - will have to assess what he has at his disposal before Wednesday night's home game against Hibernian.
Right-back Mikael Lustig stayed in at the interval with an Achilles problem, leaving new signing Jeremy Toljan to make his debut.
Edouard, who had replaced Oliver Burke, was taken away on a stretcher after being injured in a challenge from Saints skipper Joe Shaughnessy, Forrest went off with a tight hamstring and Ajer will be suspended for the Hibs game.
"If you watch the replay again, the boy Shaughnessy's stretching and his foot is accidental as Odsonne's gone to hit it," Rodgers said of Edouard's injury.
"These modern boots are not so tough. It's just caught him right on the front of his foot so he's in a wee bit of pain but hopefully he will be okay.
"James is more of a worry, he felt his hamstring a bit tight. We had to play the last 10 minutes or so with 10 men. It was Ryan's ribs - he got a bang on the ribs and could hardly breathe.
"We'll make do. We have some outstanding players who can play in those positions. We will assess it on Monday and see where we're at."