Jamie Vardy grabbed a hat-trick as the Foxes came from behind at the Etihad Stadium to stun Guardiola’s men 5-2 and storm to the top of the Premier League.
It was the first time Guardiola had seen one of his teams concede five goals in his glittering managerial career and was all the more frustrating after they dominated the early stages.
Guardiola said: “We played really good in the first 30 minutes. They defended so deep, so it was not easy, and I think the problem was that we put extra pressure on ourselves to score the second or third when they just didn’t want to play.
“They just wanted to defend and play on the counter-attack and in that position we have to be more calm, just try to be patient.
“After 1-1 and 2-1 we were not strong enough to be stable, to be patient. Even at 2-5 they settled back there with 11 players and it is so difficult to create chances.”
City started superbly with Riyad Mahrez scoring after four minutes against his old club but, despite controlling possession, they failed to add to their lead.
Vardy levelled after winning a penalty on a breakaway, then flicked in a superb second early in the second half. He completed his treble with a second penalty before James Maddison came off the bench to curl in a sublime fourth.
Nathan Ake pulled one back after Liam Delap headed against the bar on his Premier League debut but Youri Tielemans wrapped up the scoring with yet another Leicester penalty.
Leicester manager Brendan Rodgers was in no doubt where that result ranked in his time at the club.
“It was the best result, that’s for sure,” said the Northern Irishman, who took charge at the King Power Stadium in February last year.
“I think to beat Manchester City you’ve got to run like hell. You have to have that mentality that you’re going to have to work.
“I thought there was real good tactical discipline. We showed our quality, played the system very well, and it was an absolutely brilliant result and performance for us.”
On a positive note for City, Benfica have confirmed agreement has been reached for the sale of Portugal defender Ruben Dias. The 23-year-old will move to the Etihad Stadium for an initial £62million, with a potential extra £3.2million to follow in add-ons, subject to the agreement of personal terms.
City centre-back Nicolas Otamendi, 32, is set to move in the opposite direction for £13.6million.