Hear from the two heavyweights before their bout on October 19.
It is clear from the interviews above that Daniel Cormier and Roy Nelson do no like each other.
And on October 19 the men will get a chance to do something about it when they meet on the main card for UFC 166 in Houston, Texas.
In what is one of the most stacked cards of the year, UFC 166 will feature the third title fight between Junior dos Santos and reigning champion Cain Velasquez.
Also on the main card are Gilbert Melendez v Diego Sanchez, Gabriel Gonzaga v Shawn Jordan and John Dodson v Darrel Montague.