Things turned ugly quickly for Jessie Rosas earlier today (Sat., Sept. 12, 2026) at Noche UFC 4 LIVE on Paramount+ from inside Desert Diamond Arena in Glendale, Arizona, as the brother of UFC fighter, Raul Rosas Jr., suffered his first career loss at the hands of a massive Sean King knockout slam. This fight was difficult to predict on paper. While Rosas is the brother of a UFC fighter and has shown the ability to outpace his opponents inside of the cage, it was King who was the more polished wrestler with a larger frame and longer strikes. Rosas closed as a pretty sizeable betting underdog, but some believed he’s still be able to outlast King on short notice. Unfortunately for Rosas, he never got a chance to implement his offensive attack. After both fighters exchanged some leg kicks from range early on King was able to close the distance and wrap Rosas up. From there, King picked Rosas up and slammed him as hard as he could onto the canvas. Rosas looked to be out right away, but King unloaded a few hard punches to make sure. Check out the video highlights below: Sean King knocks out Jesse Rosas with a brutal slam! pic.twitter.com/FmsATyRW4f — MMA Mania (@mmamania) September 12, 2026 For more Noche UFC 4 results, coverage, and highlights click HERE.