Demetrious Johnson retirement: 'Mighty Mouse' walks away from MMA after illustrious career

Demetrious Johnson, one of the greatest fighters to ever strap on a pair of mixed martial arts gloves, announced his retirement at ONE 168 in Denver on Friday.

Johnson is an all-time great who helped establish the flyweight division in the UFC, becoming the first champion in division history in 2012 and successfully defending the title a staggering 11 times before losing a controversial split decision to Henry Cejudo in 2018. During his run, Johnson cemented himself as one of the top pound-for-pound fighters in the sport while also fighting an uphill battle as a champion the UFC often seemed disinterested in promoting.

Once the UFC championship belt was off Johnson's waist, the UFC "traded" Johnson to ONE Championship, receiving Ben Askren in exchange. The trade was further proof that the UFC didn't care that Johnson was an elite fighter who also fought in highly-entertaining bouts and scored seven stoppages in his 11 title defenses.

In ONE, Johnson won the Flyweight Grand Prix before a knockout loss to Adriano Moraes for the flyweight championship. Johnson rematched Moraes in 2022, scoring a flying knee knockout to become champion. He would successfully defend the title in a rubber match the following May.

"Like I said last time when I came to Denver, I told you guys it was potentially my last fight, and I was not lying," Johnson said on Friday night. "I am done. I am done competing in mixed martial arts, and I want to thank you guys so much for giving me the opportunity."

Johnson has not fought since his rubber match with Moraes, instead focusing on podcasting and grappling events. He may continue to compete in grappling matches for ONE but his mixed martial arts career has reached its conclusion.