Check out this video of a mountain biker, Evan van der Spuy, as he gets taken out by a red hartebeest, a member of the antelope family found in the grassland areas of Africa. The video was taken by a teammate during a race near Albert Falls Dam in South Africa.
Roughly 15 years ago I almost had a similar situation with a deer. I was riding down a hill, going about 30 MPH, when I noticed a young buck just ahead of me, standing about 20 feet off the right side of the road. I guess I spooked him as he wheeled around and was about to begin running across the road - right in my path! Fortunately, at that same time, a car was passing me on my left side, and I guess, forced the deer to change his direction. Never forgot that one....