The 41-year-old was full of compliments for the former Chile coach and played down the fact that the Basques will have just one full day's rest for the encounter at Camp Nou
The Blaugrana are six points behind Real Madrid in the race for the Liga title and Guardiola is extremely wary of the Basque side and the tactical nous of Bielsa.
"I consider him the best there is and it is a pleasure for me to face him," Guardiola said during a press conference.
"I have so much admiration for Bielsa and I try to learn from him. Athletic have been the sensation of Europe this season. They deserve the admiration of all.
"In the games I've seen, they have been a pleasure to watch. This will be a complicated game, very tough and very demanding.
Guardiola then played down the significance of the fact that Athletic will have just one day’s rest for the encounter at Camp Nou.
The Basques have only just returned home after beating Schalke 4-2 in their Europa League quarter-final clash in Gelsenkirchen on Thursday night and, under normal circumstances, they would not be asked to return to Primera Division action until Sunday lunchtime at the earliest.
However, with Barca due to face AC Milan in the Champions League on Tuesday, the meeting between the two sides will be staged a day earlier.
"The timing is what it is," Guardiola said. "It's better to have three or four days off but teams that want to reach the finals must play many matches close together and in this kind of situation.
"And we'll do well not to think that Athletic will arrive here tired. But I encourage the fans to come to the ground because it will be a very good game to see."
Barca's meeting with Athletic gets underway at Camp Nou at 22.00CET.
Between November and February, Goal.com published 10 exclusive extracts from Graham Hunter's highly anticipated new book, 'Barca: The Making of the Greatest Team in the World'. Click here to read all 10 extracts. Don't miss it!