bike race begins across albert falls game reserve in south africa. six miles in, a clearing. lead biker spots an antelope to his right. >> he says, hey, there's a buck. and then goes back to riding. all of a sudden, the buck is like, oh, are you challenging me? >> seconds later?-- >> whoa! >> he just comes out of nowhere and smashes this guy off his bike. >> almost looks like the buck grabs the biker, throws him down and it's just this massive crash of body and bike. >> i would say that's got to hurt. >> [?bleep?] >> the biker survivors with a concussion, but has no memory of the moment his buck ran out. >> holy cow!