UFC Vegas 121, also known as UFC Fight Night 289, has suddenly got a whole lot more interesting.That’s because Luis Hernandez of the Miami-Dade Sheriff’s Office has accepted a fight against convicted offender Sedriques Dumas on just two days’ notice.Hernandez earned his UFC contract on September 15 with a second-round submission win on Dana White’s Contender SeriesGettyThe 30-year-old is undefeated in eight professional bouts having started MMA in 2018GettyOn Thursday, light heavyweight Mickey Gall announced he was ‘pulled’ from UFC Vegas 121 due to a medical issue.“It sucks, I’ve overcome a lot to be here,” the American said on social media.With Gall out, UFC brass needed a new opponent for Dumas, and Hernandez has stepped in for his promotional debut without hesitation.Who is UFC’s police officer Hernandez?Hernandez, undefeated in eight professional MMA fights, punched his ticket to the UFC with a second-round submission win on Dana White‘s Contender Series (DWCS) earlier this month.View Tweet: https://x.com/hashtag/DWCS?src=hash&ref_src=twsrc%5EtfwThe 30-year-old from Florida, nicknamed ‘The Stache,’ has a 100 per cent finishing ratio since his pro debut in 2021, having wrestled in high school before transitioning into MMA in 2018.He is also the man Sean Strickland punched in the face during a Tuff-N-Uff event in July 2025, which led to a six-month suspension for the current UFC middleweight champion.What has Dumas been arrested for?Dumas, meanwhile, is on a three-fight losing streak in the UFC and hasn’t had his arm raised since August 2024.The 31-year-old, who also entered the UFC via DWCS, has been arrested 14 times in Florida since 2014, per MMA Junkie.His prior convictions include domestic battery and driving with a suspended license.MMA Mania reported in April 2025 that Dumas was arrested and booked into Escambia County Jail in Florida on five separate charges.Dumas boasts a professional record of 10-5 – but he hasn’t won since the summer of 2024GettyAccording to ESPN, Dumas was charged with home invasion, robbery, battery, possession of a weapon or ammo by a convicted felon and drug possession.The arrest came less than three weeks after ‘The Reaper’ suffered a first-round knockout loss against Michal Oleksiejczuk at UFC 314.He has since fought Zach Reese to a no contest due to an accidental foul and been submitted by Donte Johnson and Jackson McVey in his last two appearances.Weighing in for their light heavyweight contest on Friday, Dumas hit the scales at 197lbs while Hernandez came in at 204lbs.Who else is fighting at UFC Vegas 121?This weekend, the UFC is back at the Meta Apex in Las Vegas for another Fight Night show as Raul Rosas Jr takes on Raoni Barcelos in a bantamweight main event.The card will also crown the male and female winner of The Ultimate Fighter 34, which was coached by UFC Hall of Famers Daniel Cormier and Michael Bisping.View Tweet: https://t.co/nMrwR7ao2MtalkSPORT's UFC pound-for-pound rankingstalkSPORT.com has collectively voted on the best fighters to form a regularly updated UFC pound-for-pound (P4P) rankings system for the rest of 2026 and beyond.Our P4P list will be updated regularly based on performances in the Octagon — with wins, records, title wins and defences, calibre of opponents, methods of victory and much more all determining who makes it.UFC champions Islam Makhachev, Joshua Van and Sean Strickland feature – but big stars such as Alex Pereira and Tom Aspinall miss out.Azerbaijan’s Muhammadali Osmanli takes on Kyrgyzstan’s Ilimbek Akylbek in the men’s bantamweight finale while American women’s strawweight Melissa Amaya fights Tina Black of Brazil.