At a truck series race in Canada on Sunday, a NASCAR driver named Max Papis collided with another driver named Mike Skeen while they were battling for third place.

And Skeen's girlfriend was so angry about it after the race, she walked up to Papis . . . and SLAPPED HIM, which was caught on video.  Papis claims the slap actually dislocated his JAW.  But when you watch it, that doesn't seem possible.