He's simply a tough guy to beat.
What Josh Koscheck (15-4) brings to the table: Josh Koscheck is a very explosive athlete himself, which is what makes this fight so interesting. If you were to search far and wide for a man with athletic skills in the welterweight division that could rival St. Pierre's, that search would likely end with him. On top of this, he possesses solid technical striking skills with a lot of power, great wrestling capabilities, and is really above average in every area of MMA.
Georges St. Pierre vs. Josh Koscheck Prediction: St. Pierre possesses somewhat more technical striking skills than his adversary, which should lend to him being able to stay out of harm's way and score points on his feet. That said, if Koscheck lands a haymaker, it could be 'good night Irene'. So there is always the chance he could lose on his feet.
That said, the winner of this fight will be determined by who is able to impose their will via the ground game. The first time these two fought, St. Pierre took his adversary down at will and controlled him there. This time, expect there to be more stand up, as the takedowns won't come as easily to him. But in the end, their first fight was no fluke. In other words, St. Pierre is the better wrestler, and he will utilize these skills on his way to a decision victory.
Georges St. Pierre defeats Josh Koscheck by decision.


