Why isn't this fight ranked number one? It did, after all, end in Brock Lesnar becoming a UFC champion. Well, Lesnar's fight with the legendary Randy Couture lasted just two rounds at UFC 91 and ended by way of TKO. It was a great fight for Lesnar, and got him a win over a Hall of Famer. Thing is, Couture was undersized for heavyweight, and while it was a solid win, it's a fight Lesnar should have won at that point. Fans already knew he was legit, though many who were hostile to the idea of a pro wrestler coming in an beating legit MMA guys didn't want to admit it. In all, it was a reminder that simple athletics can go a long way. Lesnar really is a physical specimen, and got into the MMA game late. Just imagine what he could have done had he started sooner.