MMA star Charles Oliveira to face silent killer at UFC Rio

In a major UFC shakeup, Charles Oliveira has been handed a dangerous dark horse opponent for UFC Rio in October. Rafael Fiziev has withdrawn, and No. 7-ranked lightweight Mateusz Gamrot steps in.

UFC officially announced the news on Tuesday. Their lightweight main event concludes on October 11, where Oliveira will put his No. 3 lightweight ranking on the line, while Gamrot arguably fights for title contention.

"Mateusz Gamrot, that's the guy we're going to war with," Oliveira announced in a video posted to UFC Brasil. "The rest [of the fighters] just wanted hype, they just wanted to talk nonsense."

NEW MAIN EVENT ALERT 🚨@CharlesDoBronxs will now face @Gamer_MMA at #UFCRio on October 11! 🇧🇷 pic.twitter.com/q9fxMkg50M
— UFC (@ufc) September 23, 2025

Mateusz Gamrot's immediate reaction to securing Charles Oliveira fight

Gamrot had called out 'Do Bronx' for a short-notice opportunity, and was ecstatic to find he'd be stepping up in three weeks' time.

He could barely contain his excitement in a video posted on Tuesday night.

Mateusz Gamrot was HYPED after finding out he’ll be fighting Charles Oliveira at #UFCRio in 3 weeks 😂

🎥 @Zabooor

pic.twitter.com/fkQbTcVW1h
— Championship Rounds (@ChampRDS) September 23, 2025

Who's fighting at UFC Rio de Janeiro?

Oliveira's homecoming event will continue with 13 fights, subject to change.

Main event

Charles Oliveira vs. Mateusz Gamrot; lightweight

Main card

Deiveson Figueiredo vs. Montel Jackson; bantamweight
Jhonata Diniz vs. Mario Pinto; heavyweight
Vicente Luque vs. Joel Alvarez; reported welterweight
Gabriel Bonfim vs. Randy Brown; welterweight
Valter Walker vs. Mohammed Usman; heavyweight

Prelims

Lucas Rocha vs. Stewart Nicoll; flyweight
Vitor Petrino vs. Thomas Petersen; heavyweight
Julia Polastri vs. Karolina Kowalkiewicz; strawweight
Irina Alekseeva vs. Beatriz Mesquita; bantamweight
Jafel Filho vs. Clayton Carpenter; flyweight
Lucas Almeida vs. Michael Aswell; featherweight
Ricardo Ramos vs. Kaan Ofli; featherweight

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