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Athletic Bilbao's triumph over Manchester United in the Europa League was not quite as big a surprise to Barcelona manager Pep Guardiola as it was to many others.

In a press conference on Friday, Guardiola admired Bilbao manager Marcelo Bielsa saying, "Bielsa is currently the best coach on the planet. We're lucky to have him in La Liga so that we can learn from him. [Bilbao's] qualification is a gift for the game."

The Barcelona manager is not a recent convert to Bielsa fandom.

In November of last year, he voiced his admiration for the Argentinian tactician ahead of a league match-up.

At that time Guardiola said, "Bielsa's teams are authentic, different and unique. The only way we can win in San Mames [Athletic Bilbao's stadium] is to show more courage than them."

Despite his open admiration for Bielsa, Guardiola will be looking to get the better of "the best coach on the planet" when their sides face off in the Copa del Rey final on May 25th in Madrid.