This was the fight that everyone wanted to see. The fight that was hyped as the real main event prior to Georges St. Pierre dropping off the card due to a knee injury. In the lead up both fighters were incredibly respectful of the other's skills and never committed to the usual trash talk. It was only at the weigh ins that they showed even the slightest hint of animosity with Diaz and Penn going nose to nose on stage before Dana White jumped in to split them apart.
The fight was everything the fans hoped it would be, with both fighters coming forward in the first round looking to put the most hurt on the other. The clear aggressor was Penn who found his range early and head hunted Diaz the first five minutes. In the second round Diaz took over, forcing Penn against the cage and just battering him with punches in bunches. Penn's face showed the cumulative damage going into the final round and he was unable to keep up with the pace that Diaz set. There were times when Penn was landing well, he just wasn't able land with the same pop that he had in the first.
The judges scored the fight for Diaz who celebrated by calling out Georges St. Pierre making the claim that the champion wasn't actually hurt and was instead ducking everyone. To his credit St. Pierre didn't let the trash talk get to him.
This was the first time in his career that a fighter made B.J. Penn look old. He retired in the post fight and if this truly was the last time that fans will see the Hawaiian, he went out on his shield. He never backed down and stayed in the fight all the way to the final bell.