He told TV3: "I remember when I went out to the pitch I saw the tension in the faces of the Athletic Bilbao players. The Barça players, on the other hand, seemed to be playing a friendly match. They were used to it. They knew they would win."
Barca won 3-0 and Guardiola denies claims there was an agreement between the two teams that Barca would go easy on Bilbao after the third goal.
"I would tell you with complete certainty that it was not like that. Marcelo Bielsa's teams are educated in resilience and never give up. And those Barça players, if they could score five goals, they did, and if they could score eight, they scored eight. They were very good people, but on the field they were f***ing assassins."