Rose Namajunas reacts after defeating Zhang Weili of China in...

Rose Namajunas reacts after defeating Zhang Weili of China in their women's strawweight championship bout at UFC 261 at VyStar Veterans Memorial Arena on April 24, 2021 in Jacksonville, Florida. Credit: Zuffa LLC/Josh Hedges

A look at which UFC weight classes have crowned new champions thus far in 2021.

UFC bantamweight champion: Aljamain Sterling

The Uniondale-raised Aljamain Sterling won the belt from Petr Yan after Yan was disqualified for throwing an illegal knee to the head of Sterling, who was a downed opponent, late in the fourth round. It was the first time a UFC title changed hands via disqualification. Yan was up on two of the three scorecards through the first three rounds, 29-28, 29-28, 28-29, and likely would have won the fourth round if not for committing the illegal strike.

UFC heavyweight champion: Francis Ngannou

Potential reaches actual as Francis Ngannou finally became the UFC heavyweight champion when he knocked out Stipe Miocic in the second round at UFC 260 on March 27. Ngannou, who lost decisively to Miocic the first time they fought for the title in 2018, dropped Miocic twice in the second round, the last of which buckled Miocic's knees to stop the bout.

UFC women's strawweight champion: Rose Namajunas

Rose Namajunas won back her title when she knocked out Zhang Weili at the 1:18 mark of the first round at UFC 261 on April 24, 2021. Namajunas landed a left high kick that floored Weili, and then she followed up with a few strikes before the fight was stopped.

UFC lightweight champion: Charles Oliveira

With his ninth straight victory, Charles Oliveira won the vacant UFC lightweight title at UFC 262 on May 15. Known more for his submissions, Oliveira beat Michael Chandler by TKO in the second round. "Do Bronx" dropped Chandler with the left as the second round opened, then chased him around before landing another left hook and follow-up strikes 19 seconds into the round.

UFC flyweight champion: Brandon Moreno

At UFC 263 on June 12, Brandon Moreno became the first Mexican-born champion in UFC history. He submitted Deiveson Figueiredo via rear naked choke in the third round to take his title in their rematch. Moreno started strong, hurting Figueiredo with a big shot in the first round. Moreno also reversed a takedown in the second round before getting the submission midway through the third round.

UFC interim heavyweight champion: Ciryl Gane

Four-plus months after Francis Ngannou became the heavyweight champion, the UFC put together an interim title fight between Ciryl Gane and Derrick Lews. Gane remained perfect in the UFC with a third-round TKO of Lewis at UFC 265 in Houston on Aug. 7 to become the interim champion and set himself up for a title unification bout with Ngannou.

UFC interim bantamweight champion: Petr Yan

Petr Yan lost his title earlier this year to Aljamain Sterling (see above), but got back a piece of the gold at UFC 267 in Abu Dhabi on Oct. 30. He and Cory Sandhagen put on a terrific performance, with Yan winning by unanimous decision. All three judges scored it 49-46 for the Russian bantamweight.

UFC light heavyweight champion: Glover Teixeira

Glover Teixeira became the oldest first-time UFC champion when the 42-year-old Brazilian took the title from Jan Błachowicz at UFC 267 on Oct. 30. Teixeira controlled most of the first round, then scored a takedown in the second round and worked toward a submission chokehold to claim the title at the 3:02 mark in the main event in Abu Dhabi.

UFC women's bantamweight champion: Julianna Pena

Julianna Pena told anyone and everyone with a microphone that she was ready to dethrone Amanda Nunes as bantamweight champion. At UFC 269 on Dec. 11, she did exactly that -- and as a 10-1 underdog. Pena submitted Nunes, a two-weight champion widely considered the best female MMA fighter ever, by rear naked choke in the second round in the co-main event at T-Mobile Arena in Las Vegas.

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