The Whites went 2-0 up and lost control as Birmingham hit back to level, before Leeds hit the front another three times for a 5-4 win.
Bielsa quipped: “I am alive,” after the game, when questioned over the state of his heart.
But everything he knows to be true about his side appeared to go out the window in a crazy game.
“All the previous analysis about our team, we saw the opposite,” he said.
“We had high efficiency to score and we are a team that needs a lot of chances to score. We didn’t have safety in defence. We have conceded goals that normally we would think we’re in good condition to avoid.”
Failing to manage the match at 2-0 up led to remarkable scenes.
Bielsa wanted more control and admitted the attacking spirit of his side was both their downfall and their saving grace.
“We should have controlled the match better in the first half,” he said.
“It was difficult. In the first part of the second half the match had no definition, even though we improved.
“After 2-2 the match was strange. It was goal for goal. The spirit of the team.
“Every time Birmingham scored we had energy to go for one more goal.”
Report: Page 3