Valter Walker made his third octagon appearance of 2025 at UFC 321, where he captured the attention of fans with his performance and interview.Walker faced Louie Sutherland in the preliminary card at the Etihad Arena in Abu Dhabi. The bout saw the Brazilian fighter quickly dominate his opponent by securing victory with a submission in the opening round. Notably, this marked Walker's fourth consecutive win in the UFC through a heel hook.Check out Valter Walker's finish below:Several fight fans and netizens went to the comments section of Full Send MMA's post on X to share their reactions, with one user writing:"We live in a simulation, but it's a good one."Following the victory, Walker also took a verbal jab by calling out fellow heavyweight fighter Chris Barnett with an interesting name. Another fan took notice of that and wrote:"That was funny!!!"Others commented:"Ffs I missed it but that hilarious""The man performed this operation in his stomach. I have no other explanation!""Lame callout honestly why’s he not going for the top 15?""Valter Walker adding excitement to the heavyweight division one heel-hook at a time. This guy is awesome. #UFC321"Check out more fan reactions below:Fans' reaction to Valter Walker calling out Chris Barnett after securing a submission win at UFC 321. [Screenshots courtesy: @full_send_mma on X & Respective X handles]With this victory, Walker extended his winning streak to four fights. Before defeating Sutherland, he had wins against Kennedy Nzechukwu, Don'Tale Mayes, and Junior Tafa. In all these fights, the Brazilian won via heel lock submission.Meanwhile, Sutherland experienced defeat in his promotional debut at UFC 321. Looking ahead to his next fight, Walker has expressed a desire to face Hamdy Abdelwahab, who fought Barnett on the same card before Walker's match against Sutherland.