Not sure if he started fighting stupid. He never gave Bigfoot any respect in that fight, and had his hands down the whole fight. Overeem also gasses, Bigfoot an even bigger man had much more left come round 3.
2 wrestlers beat Bigfoot to a bloody pulp. DC at 5'10 and still a green striker clocked Bigfoot standing and sent him down. You would think the K-1 champs with all of this supposed power could do the same in 3 rounds.