Conversation so far:
What is the Pistons roadblock referring to?
despite pushing the series to seven games, the Bulls lost to the Pistons for the third consecutive season.
What year did the Bulls lose to the Pistons for the third consecutive season?
the 1989-90 season.

Question: Who was their coach at the time?
Self-contained rewrite: Who was the Bulls coach at the time of the 1989-90 season?