The 57-year-old was confident in the tactics he set out against the Blaugrana and was delighted to see his side reap the fruits of their labour
Tito Vilanova's men thought they had secured victory after Lionel Messi came off the bench to score and then set up Alexis Sanchez's strike, but Ander Herrera's 90th minute effort thwarted the visitors' title celebrations.
And while Bielsa acknowledged it was impossible to beat the Blaugrana at their own game, he also suggested the San Mames outfit countered the runaway league leaders impeccably through their tactics.
"I am very pleased with how this tie went," the 57-year-old proclaimed after the match. "The efforts of our players deserved more than dignified defeat.
"The only way we can close the gap on a team like Barcelona is by playing defensively and preserving our energy to attack.
"Their goals in such quick succession pre-supposed our decline, but we reformed our balance, got close to their area and eventually found the answer. We've strengthened our concept as a team."
The Basque club have endured their struggles this season, with the departure of Javi Martinez and Fernando Llorente's first-team exile condemning them to 14th place in La Liga.