By the time Anthony Pettis defends his UFC lightweight championship on December 6, it will be 15 months since he last stepped into the octagon. Still, "Showtime" doesn't see his fight against top contender Gilbert Melendez lasting more than one round.

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After winning the lightweight title in August 2013, Pettis was sidelined with a knee injury that held him out of action for a year. He would've been able to return sooner but he and Melendez signed on to coach the current season of "The Ultimate Fighter," pushing their fight to UFC 181. While Pettis has been out of action he's had to listen to doubters and naysayers, so he will have something to prove when he returns.

"The fans can expect me finishing this fight in the first round," Pettis told Combate.com, according to BloodyElbow.com. "I've been out for a year and I'm excited to be back. I'm healthy, ready to fight and, unfortunately, Melendez will be my first opponent after my return. I say unfortunately because I'm sure that I won't need more than one round. I have to shut up a lot of people and I have others to face."

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Pettis has no bad blood with Melendez, as the two pretty much avoided each other throughout the season of "TUF." But he has had to field barbs from other contenders, namely up-and-coming lightweight Khabib Nurmagomedov. Pettis said he is focused on facing Melendez, but he welcomes the opportunity to get his hands on Nurmagomedov.

"Gilbert is a cool guy but we haven't chatted so much during the season and we haven't had any arguing. He was there to be a coach and so was I," Pettis said. "I'm a fighter and I have a belt for a reason. I got injured and couldn't train like I wished but I'm back. When Khabib's time comes, we'll fight. Now I have Melendez in front of me and that is my concern but if Khabib is next, we'll fight."