When I retired from mixed martial arts (MMA) in late 2017, I actually meant it. I wasn’t playing a game. I was thirty-three years old, undefeated, and a reigning champion, but I was fresh out of real challenges at ONE Championship, the Singapore-based promotion I was fighting with. Before MMA I was a two-time national champion at the University of Missouri, twice winning the Hodge Trophy as the country’s best collegiate wrestler. Under the circumstances, walking away felt like the right thing to do. It was something I could control.
