Justin Gaethje is eyeing a Khabib Nurmagomedov clash, insisting there is "no other challenge I want right now" after crushing Tony Ferguson at UFC 249.

Gaethje became the interim lightweight champion after scoring a brutal final-round stoppage against Ferguson in Jacksonville, Florida on Saturday.

The UFC made its long-awaited return behind closed doors amid the coronavirus pandemic, which prevented the event from taking place on the original date of April 18 in Brooklyn.

Travel restrictions also stopped unbeaten lightweight holder Khabib from fighting in the United States, leading Gaethje to fill the Russian's void against Ferguson.

After snapping Ferguson's 12-fight winning streak and leaving his fellow American bloodied, Gaethje (22-2) turned his attention to Khabib.

"Khabib is the best in the world," Gaethje said in the octagon afterwards.

"I've been working since I was four for challenges like this and I'm happy to represent the United States of America against Dagestan or Russia's best.

"He's 28-0 and there's no other challenge I want right now. I want to fight him."

Gaethje stepped up to meet Ferguson in the octagon and he dished out relentless punishment to stun the former interim holder in a wild contest.

Ferguson was left bloodied and bruised as a jab to the head shocked the veteran, prompting the referee to crown Gaethje winner by TKO in the fifth round.

Gaethje was the aggressor from the outset in the main event at VyStar Veterans Memorial Arena, where Ferguson – while absorbing all the strikes – took one too many strikes to the head, body and legs.

"I told my coaches, 'You're not gonna like it, but I'm ready to die tonight,'" Gaethje, who extended his winning streak to four, said afterwards. "That's the mentality you have to come in there with."

Ferguson (25-4) added: "Justin is a tough son of a b****, I'll be real. I was prepared for Khabib, not a striker."