Conor McGregor
At UFC 194, he defeated Jose Aldo to win the UFC featherweight championship. In his welterweight debut at UFC 196, he  was defeated by Nate Diaz in the second round via submission. On 6 October 2018, he won the UFC lightweight championship by defeating Eddie Alvarez and won via KO. In his boxing debut in 2017, he  was  defeated by Floyd Mayweather Jr.. He returned to MMA in 2018 and was defeated by Khabib Nurmagomedov via submission at UFC 229. The event set the record for the biggest MMA pay-per-view event, with 2.4 million buys in the United States. Throughout his career, McGregor has become the subject of many controversies due to his behaviour.