UFC 282 was unable to crown a new light heavyweight champion on Saturday with a tough five-round split draw in the main event between former champion Jan Blachowicz and Magomed Ankalaev in Las Vegas.

Blachowicz had appeared to concede defeat immediately after the fight by raising Ankalaev's hand, but it was deemed a split draw by the three judges with Mike Bell and Derek Cleary going either way and Sal D'Amato scoring it 47-47.

Ankalaev, who was on a nine-fight winning streak, finished the stronger of the two, with his final-round score ensuring the split decision. The Dagestani was dismayed that he was not awarded the win by the judges.

"I don't know what to say," Ankalaev said through a translator. "I won that fight. Why didn't I get my belt? I don't know what to say.

"I don't know if I'm going to fight for this organization again, because I don't know what just happened."

Blachowicz said he had not done enough himself to win the fight and returned to the cage to call for the UFC to "give the belt to Magomed Ankalaev".

"I have to watch the fight, but for sure I didn't win," the Pole said. "I don't know if I lost the fight, but I'm not the winner."

The bout was full of momentum swings with Ankalaev going with a wrestling strategy from the fourth round, having hurt his lead right leg in the second round from Blachowicz kicks.

Ankalaev out-landed Blachowicz 191-79 in total strikes and 78-55 in significant strikes.

UFC president Dana White announced after the fight that Glover Teixeira would take on Jamahal Hill for the vacant light heavyweight title at UFC 283 next month in Brazil.

There was also controversy in the main card lightweight fight won by Paddy Pimblett over Jared Gordon, with the Englishman winning by unanimous decision (29-28, 29-28, 29-28).

Gordon won total strikes 100-97 and successfully completed three takedowns, yet Pimblett had the decision go his way.

"Coming into the third I knew I won the first two rounds easily," Pimblett said after the fight.

When asked if it was close, he added: "No it wasn’t, that wasn't close."

Earlier, Mexican 18-year-old Raul Rosas Jr triumphed as he became the youngest fighter ever to compete in the UFC, beating Jay Perrin with a first-round submission in the bantamweight during the preliminary cards.

Glover Teixeira defied father time as the evergreen veteran sensationally upset Jan Blachowicz in their light heavyweight title fight at UFC 267 to become the oldest first-time champion.

Teixeira showed age is no barrier after the 42-year-old forced defending champion Blachowicz into a rear-naked choke submission in the second round of Saturday's main event in Abu Dhabi.

Blachowicz (28-9) was making his second title defence and riding a five-fight winning streak before being stopped in his tracks by the evergreen Teixeira.

Teixeira (33-7) last had a chance at a UFC light heavyweight title seven years ago and lost to then-champion Jon Jones.

"Never give up on your dreams, no matter what people say, don't listen to them," Brazilian fighter Teixeira said afterwards. "They're gonna put you down.

"Don't listen to those negative people. Believe in yourself.

"I'm breaking the rules, 42 years old. And I'm gonna keep breaking the rules."

UFC president Dana White added: "Glover Teixeira is and has been one of the toughest guys in the division for a very long time, this was his dream forever to get this title shot.

"He finally gets it and did it tonight."

Blachowicz was coming off his first title defence, a unanimous decision victory against previously undefeated middleweight champion Israel Adesanya at UFC 259 in March.

"I think I left legendary Polish Power in the room," Blachowicz said.