Firstly, the sherdog record isn't entirely accurate. I don't give them much credit for following lesser known fighters.
All of this guys wins over decent fighters are guys who weigh 20 pounds less than him at their natural weight. Don't ever try and put rich and bonnar on the same level.
You have brought up a really good question. The guy is a kind of fighter that doesn't exist in the UFC or pride. He's what's called an enforcer. Essentially, he gets fights with up and comers in much lower weight classes, padding his record. His fights are stacked in his favor, as an attraction for WFA.
Guys like this are under high paying contract with small time organizations and they exist so that WFA can say "we have a guy who beat rich franklin and BJ Penn." They forget that fighting at natural weight the guy is 20 pounds heavier than franklin and 35 pounds heavier than Penn.
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