Clyde Drexler ain't been on the job for a week as BIG3 commish -- and he's already makin' history -- hiring the 1st ever female as head coach of a men's pro basketball team ... TMZ Sports has learned.
"The Glide" tapped Nancy Lieberman -- a member of the Naismith and Women's Basketball Hall of Fame -- to coach Power, the squad he previously coached before leaving to run the league.
Lieberman -- a legend for her hoopin' on the court -- isn't a novice to coaching either. She was an assistant coach with the Sacramento Kings .