A big lightweight division fight has been added to the UFC 166 card as Gilbert Melendez will face Diego Sanchez. Melendez is currently winless in UFC competition, but he is the former Strikeforce Lightweight Champion. Sanchez has won three of his last four under the UFC banner, with a notable victory over Martin Kampmann at UFC On Versus III. UFC 166 takes place on October 19th from the Toyota Center in Houston, Texas with Cain Velasquez and Junior Dos Santos headlining.