Russell Westbrook -- Hits Hollywood Nightclub ... Night Before Wedding

Talk about a last minute bachelor party ...

Hours before he tied the knot, NBA superstar Russell Westbrook hit up 1 OAK nightclub on the Sunset Strip with some of his famous friends ... and TMZ Sports has the footage.

Westrbrook -- sporting a pretty sweet suit (with a pocket square) -- had a posse with him that included Kevin Durant.

But don't worry, despite the fact Westbrook's fiancee was nowhere to be seen, sources in the club say the guys were just having a great time by themselves -- "No funny stuff."

He left the club around 2 AM -- and hours later, got married on Saturday at the Beverly Hills Hotel.