Tony Parker & French Basketball Team -- Drown 6th Place Sorrows ... in $20k of Liquor

You're bad ass NBA player Tony Parker ... but you're French National Team just BLEW the Olympics and walked away in 6th place ... what do you do? Party your face off with $20,000 worth of booze ... that's what.

It all went down at Chinawhite Nightclub in London ... San Antonio Spurs studs Tony Parker and Boris Diaw rolled in with their French team Thursday night ... a mere 24 hours after losing to Spain and sealing their elimination from medal contention.

Parker, Diaw and the rest of Team Frenchy popped multiple bottles of Cristal and a magnum-sized Veuve Clicquot ... along with other effective libations.

And they didn't party alone ... sources tell us several members of Germany's women's volleyball team were kickin' with the baskeballers.

When it came time to pay the bill, we're told the honor went to Boris Diaw ... who even left a $2,000 tip.