Does anyone remember watching this guy in his prime. He was just a huge ripped 280 at 6'3". I think he would have taken to MMA well.
I don't think anyone now can, but I think with lettle training he would have just overpowered Fedor.
If you don't remember him, do some searches.
http://www.answers.com/topic/alexander-karelin
The only wrestling match he lost was where the guy scored one point and then avoided him.