Israel Adesanya retained his middleweight title after humbling undefeated Paulo Costa via a second-round TKO at UFC 253.

UFC star Adesanya and Costa put their 100 per cent records on the line and fought for the middleweight belt at "Fight Island" in Abu Dhabi on Sunday.

There had been plenty of pre-fight jibes, with Costa (13-1) accusing Adesanya (20-0) of ducking the challenge of former light-heavyweight champion Jon Jones.

But Adesanya silenced Costa, who was hit with a counter-punch in the second round and never recovered in a one-sided contest in the octagon.

Nigeria-born New Zealander Adesanya dominated from the outset, attacking Costa's left leg from the first 10 seconds and it set the tone.

Costa – whose four wins in UFC had come via way of KO/TKO – tried to respond and landed a couple of kicks as the pair tested each other.

Adesanya wore Costa down, with bruising visible on Costa's leg at the start of the second round before the former opened a cut on his opponent's head.

With victory in sight, Adesanya got on top of Costa as he dropped to the canvas and struck relentlessly until the referee intervened and stopped the fight.

After his underwhelming win over Yoel Romero in March, Adesanya said: "I've been telling you guys. Like Roy Jones said, ya'll must have forgot. Ya'll must have forgot.

"I see you media people with your little clickbait headlines. I had to make ya'll remember."

Meanwhile, Jan Blachowicz stopped Dominick Reyes to win the vacant light-heavyweight crown in the co-main event.

Blachowicz triumphed via TKO in the second round as the Polish fighter became the first man other than Jones or Daniel Cormier to hold the title since 2011.

"The only thing in my mind is, Jon Jones, where are you?" Blachowicz said after Jones vacated the title. "This is how we do it in Poland. I'm waiting for you."