I respectfully disagree about the rut season being a factor. If Red Hartebeest are like North American Deer, they will panic and run from relative saftey into the side of moving vehicles or directly into the path of a moving vehicle. If the deer was truly on the attack, the rider would have ended up in the hospital. If you have ever encountered a tamed deer that will interact with people - as I have - you would be amazed at their power. A large buck can kill a man quite readily.