Kamarudeen Usman is a Nigerian American former freestyle wrestler and professional mixed martial artist. At present, he is affiliated with the Ultimate Fighting Championship (UFC), where he competes in the welterweight division. He is a former UFC Welterweight Champion and the winner of The Ultimate Fighter 21 tournament. Born in Nigeria to a middle-class family, he had a modest upbringing. His family moved to America when Kamaru was a child. While neither of his parents had any particular interest in wrestling or mixed martial arts, the young boy developed a passion for sports and started wrestling in his sophomore year as a high school student. He excelled in his amateur wrestling career, compiling a 53–3 record as a senior. He continued wrestling in college and made it to the US University World Team in 2010. However, he suffered from injuries that forced him to abandon his wrestling career. He then turned to mixed martial arts and joined UFC, where he proceeded to build a brilliant career as a mixed martial artist. As of mid-2022, he was ranked No. 1 in the UFC men's welterweight rankings. His brother is also a mixed martial artist.