Prince Throws Private Concert ... For WNBA Champs!

Prince went crazy Wednesday night ... throwing an insane invite-only concert for one of his favorite teams -- the WNBA's Minnesota Lynx -- and he was so pumped, he played for 3 HOURS!!!

It all went down at Paisley Park in Minnesota -- where roughly 150 people, including players, personnel and Target Center staffers, watched His Purpleness jam out to hits like "Purple Rain" and "Let's Go Crazy" ... according to the Star Tribune.

The show began at 12:30 AM and didn't wrap up until roughly 4 AM.

Prince is a HUGE Lynx fan -- he attended the WNBA championship ... and during his concert, he congratulated the ladies while putting signs that read "2015 WNBA Champions" on the video screens.

And if the performance wasn't cool enough already -- the band also broke out a Princeified rendition of "We Are the Champions."