The Premier League champions get their European campaign underway against the German outfit at the Etihad Stadium after a crucial win over Leicester City at the weekend.
With City set to play five times in the space of two weeks before the end of the month, Guardiola will be looking to shuffle his pack after his side have recovered from a shaky start to the season with three wins on the spin.
However, ahead of City's Champions League group-stage opener against Leipzig, the Catalan boss is not downplaying the danger posed by the Bundesliga side, who will be aiming to bounce back after suffering a 4-1 defeat at the hands of Bayern Munich on Saturday.
Previewing City's upcoming tie against Jesse Marsch's side, Guardiola said: "The most difficult game we have will be the first against Leipzig," as quoted by the club's official website.
"This (vs Leipzig) is the most important game in the group stage. I don’t think (for) one second about PSG, because the teams we are going to face in the group stage are so, so difficult.
"Leipzig in Germany have not always been a contender for Bayern (Munich), but Bayern are unstoppable. I know the rhythm, quality, the pace they (Leipzig) have."
The Sky Blues sealed a narrow win at the King Power Stadium on Saturday, with Bernardo Silva's goal just past the hour mark helping City claim a narrow win against the Foxes.
Guardiola added: "It (Leipzig) will be a good test, but it’s important to arrive in this test the way we’re playing now and do a good game."
City will return to league action at the weekend against Southampton before hosting Wycombe Wanderers in the FA Cup next week.
