Unbeaten lightweight champion Khabib Nurmagomedov retired from mixed martial arts after stopping Justin Gaethje with a triangle choke early in the second round at UFC 254 on Saturday night. Nurmagomedov (29-0) made the announcement immediately after he impressively finished his first fight since the death of his father and lifelong coach in July. Abdulmanap Nurmagomedov had a heart problem exacerbated […]