Heavyweight champion Cain Velasquez will step into the Octagon for the third time against Junior dos Santos at UFC 166, and he vows it will be the last.

The 31-year-old title holder has built a storied rivalry with his Brazilian counterpart—one which has played out over the course of the past two years—and provided a pair of exhilarating moments in the careers of both men.

Cigano scored a flash, first-round knockout victory in their first meeting at UFC on Fox 1 back in 2011, and Velasquez reclaimed his title in epic fashion by putting a five-round beating on the heavy-handed Brazilian just north of a year later at UFC 155. The AKA staple's victory in Las Vegas put the series at "one all," and opened the door for the all-important "rubber match" to determine who will rule the heavyweight division going forward.

That particular juncture will come on Oct. 19 in Houston, and Velasquez is determined to put a definitive stamp on their trilogy. In his mind, there is no end in sight for his title reign. That being said, Velasquez is also well aware that he will need to put dos Santos away once and for all in order for his career to move forward.

The opportunity to do just that will come when the two heavyweight juggernauts square off in Houston at UFC 166, and Velasquez believes a victory over the former champion will deliver a conclusive final chapter to their saga.