Khabib Nurmagomedov extended his perfect professional record as he retained his lightweight title at UFC 254 in Abu Dhabi - then announced his retirement.

Russian Nurmagomedov, 32, defeated interim champion Justin Gaethje with a second-round triangle choke submission to claim a 29th victory and unify the 155lb title.

Nurmagomedov said he had honoured the memory of his father, coach and mentor Abdulmanap, who died in July following complications arising from Covid-19.

Despite many believing Nurmagomedov would chase his 30th professional win before contemplating retirement, the emotional champion asked his team-mates to cut his gloves off before quitting.

"It was my last fight. There's no way I'm going to come here without my father," he said. "It was the first time after what happened with my father, when the UFC called me about (fighting) Justin, I talked with my mother for three days.

"She didn't want me to fight without father, but I promised her it was going to be my last fight, and if I give my word, I have to follow this. It was my last fight here.

"I know only one thing I want from the UFC: Tuesday, you guys have to put me number one pound-for-pound fighter in the world because I deserve this.

"Undisputed UFC lightweight champion, 13-0, 13 in the UFC, 29 in my pro MMA career. I think I deserve this."