Conversation so far:
When did Oscar Robertson play for the Bucks?
Prior to the 1970–71 season, the Royals stunned the basketball world by trading Oscar Robertson to the Bucks for Flynn Robinson and Charlie Paulk.
what position did Oscar Robertson play for the Bucks?
Oscar Robertson played Point guard for the Bucks

Question: who was his coach?
Self-contained rewrite: who was Oscar Robertson's coach before the Bucks?