Guardiola's side make the trip to Stamford Bridge with Chelsea already being hailed as champions-elect.
Guardiola's side make the trip to Stamford Bridge with Chelsea already being hailed as champions-elect after opening up a seven-point gap over Tottenham and an 11-point advantage over City.
City boss Guardiola had always been confident that Antonio Conte, a rival he greatly admires, would transform Chelsea's fortunes in his first season at the Bridge.
What he did not expect was the luckless December reverse that proved a setback from which City's own title challenge never recovered.
From 1-0 up and a glaring Kevin De Bruyne miss away from a comfortable lead, City were not only undone by Chelsea's ruthless counter-attacking game but had Sergio Aguero and Fernandinho sent off in an unedifying finale that brought bans for the players and a fine for the club.
Instead of overtaking their rivals that December day, City trailed Chelsea by four points and the course of the season was set in a devastating blow to Guardiola's ambitions for his debut season.
"We finished the game against Chelsea four points down and, believe me, I watched the game many times," Guardiola said.
"We were much, much better. I'm sorry, Antonio, but we were. We deserved to win.
"At that moment it was one point, then we go to Leicester (the following game) without Sergio... another three (points behind) and soon it's 10 points. These are minimum details.
"There were unbelievable penalties that did not happen in that game, and many other things.
"All the teams want to make a counter-attack against us. Chelsea are good at set pieces and in the positional game, they are one of the best teams when it comes to using the third man and to set the ball in attack and runs in behind.
"They are so dynamic, they are good at the positional game, they use all the aspects of the game.
"That is why they are one of the best teams in Europe by far."
While that tipping-point game still gnaws at Guardiola, he has nothing but admiration for the way in which Conte has eclipsed both himself and Jose Mourinho, at Manchester United, with his impressive debut season.
"My opinion about my colleague Conte is that he's superb, maybe he's the best. How he was able to make Italy play beautiful football, Juventus too, in a culture where it's so defensive," he said.
"He's an excellent manager. I learn a lot when I see his teams -- Juventus, Italy and now (Chelsea). I like to do that because you see what they want to do.
"Their teams control a lot of aspects. It's a good lesson for me to see his teams and learn."
Despite the daunting gap between their teams Guardiola is not prepared to concede a title race that has been running away from him since that December defeat.
"Until you are mathematically champions, everything can happen. It’s done when it’s done. Until then, anything can happen," he said.