Lightweight champion Anthony Pettis and Gilbert Melendez will face off at the UFC's year-end event in December.
UFC President Dana White today made the announcement during a special press conference in Puerto Rico. Pettis and his younger brother Sergio were also in attendance.
The UFC's end-of-year event is one of the biggest of the year and typically takes place on the final weekend of December in Las Vegas.
White also "guaranteed" the UFC will run a show in Puerto Rico in 2015 and said Pettis would be involved. Pettis is of Puerto Rican and Mexican ancestry but grew up in Milwaukee.
Before Pettis and Melendez step in the cage, they'll serve as coaches for the 20th season of The Ultimate Fighter. The series features 16 female strawweights vying to become the first-ever UFC strawweight champion. The majority of the cast made the leap to the UFC when all-women's promotion Invicta turned the rights to their contracts over to the UFC.
The Ultimate Fighter 20 marks the first time a UFC championship will be contested in the reality show tournament. It will begin airing on Fox Sports 1 in October.
Pettis captured the UFC belt last year with a first-round submission of Benson Henderson. He has been sidelined by injury ever since.
Who will win this fight?
Melendez lost a close decision to Henderson in his first attempt at UFC gold last year. But he rebounded with a win over Diego Sanchez in a thrilling UFC 166 bout in October. Melendez became a free agent after the win and signed a term sheet with UFC rival Bellator when he could not come to an agreement with the UFC.
But the UFC matched Bellator's offer, keeping Melendez in the fold. The deal also likely made Melendez the highest-paid lightweight on the roster. As part of his new deal, Melendez was immediately named as the next challenger for Pettis. The coaching announcement for The Ultimate Fighter was made on the same day.