Manchester City faced fierce competition in the 2018-19 season as they narrowly edged out Liverpool to win the Premier League title.
"The toughest opponent I've ever faced in my career is this Liverpool from a year ago and this one", Guardiola told DAZN.
"If you let them to dominate you, they will cage you and you don't come out".
Guardiola believes Jurgen Klopp is the toughest manager he ever faced in his career. When you dominate them, they find running spaces like no one else does. Whether they are solid enough at the back themselves is my only question. They are very strong strategically. It will have hurt him even more that, during this time, and after he joined City, Real Madrid won the Champions League four times in five years - a sequence broken only by Barcelona, who were no longer led by Guardiola but still had his imprint.
"If you ask me which team I've had more difficulty to decipher and deal with, that's Liverpool".
The Derby midfielder added: "I saw Zinedine Zidane do it in his first spell as Real coach when he played against Guardiola-style teams in big games, and it brought him successes".
According to the Mirror, Guardiola is considered by many to be the world's best coach, however, he was unable to guide City to their third straight Premier League triumph last term. With Jose Mourinho, with [Manuel] Pellegrini, with all the coaches they have had.
'Sergio Ramos is suspended which is a huge loss to the Real defence and I think City will score.
The 49-year-old was quick to admit that he was indeed outshone by Klopp this season, as he hailed the 2019/2020 Liverpool side as being the best group of players he has come up against in his career.
'It was the first time I've seen Guardiola play like that and I've a feeling he'll do the same at the Etihad.
"I'm really glad that things are going well for him because people like him are very good for football".