UFC star Paulo Costa shows off gruesome red elbow after infection as he  undergoes surgery weeks before fight"Kamaru Usman Steps In to Face Khamzat Chimaev at UFC 294 After Paulo Costa's Withdrawal"

In a swift turn of events, Kamaru Usman has answered the call to replace the injured Paulo Costa and will now take on Khamzat Chimaev at UFC 294. Costa's surgery on his elbow just weeks before the fight rendered him unable to compete, leading to Usman's acceptance of the bout. This fight marks Usman's middleweight debut as he moves up from the welterweight division to co-headline the event in Abu Dhabi on October 21.

UFC 294 has seen rapid changes to both the main and co-main events. After Charles Oliveira's unfortunate withdrawal due to a training injury, the main event was adjusted to feature a rematch between Islam Makhachev and Alexander Volkanovski. Chimaev vs. Usman now takes the co-headliner spot following Costa's inability to compete.

Usman, widely regarded as one of the top welterweights in UFC history, strung together an impressive 15 consecutive wins before experiencing back-to-back losses to Leon Edwards. While a matchup with Chimaev was initially discussed at welterweight, the shift to middleweight paves the way for this highly anticipated showdown on October 21.

UFC 294 is set to unfold at the Etihad Arena in Abu Dhabi, with the pay-per-view commencing at a special 2 p.m. ET start time.