Olympic gold medalist boxer Claressa Shields signs multiyear deal to fight in MMA

Claressa Shields, arguably the No. 1 pound-for-pound female boxer in the world, will make her professional mixed martial arts debut in 2021.

Shields, a two-division undisputed world champion in boxing, has signed an exclusive, multi-year deal with MMA promotion PFL. The 25-year-old will not compete in PFL's traditional "season format" in 2021, but intends to fight at least twice, with an eye on a season berth in 2022. She will continue to box in 2021 as well.

"I wanted to test myself," Shields told ESPN, on her transition into MMA. "I want to see if I can be a world champion in boxing and a world champion in MMA. That's something I want to test myself on. I'm not saying boxing is easy, but I've been on top of the world for almost 14 years now."

A native of Flint, Michigan, Shields was a gold medalist boxer for the U.S. in the 2012 and 2016 Olympics. She has teased the idea of a transition to MMA for more than a year, and at one point, challenged UFC two-weight champion Amanda Nunes to a 2-fight contest consisting of one boxing match, one MMA match.

To this point, Shields says she has attended "a few" jiu-jitsu classes, and has done some work with U.S. Olympic wrestler Adeline Gray.

"I can say, it's not as bad as I thought it would be," said Shields, on the grappling aspect of MMA. "I thought I would absolutely hate it. I thought as soon as she grabbed my leg I would get frustrated and would try to bite her or something, but that hasn't happened."

The PFL postponed its entire 2020 season due to the COVID-19 pandemic, but has plans to resume its 2021 season in April in Las Vegas. The promotion offers a 155-pound lightweight division for females, and it's led by 2019 winner Kayla Harrison. Harrison also won Olympic gold in 2012 and 2016 for the U.S. in judo. Shields told ESPN she and Harrison are close friends, but would have no problem competing against each other if it ever made sense in the future. Harrison is 8-0 in MMA.

"I was telling MMA fans, I'm not just a talker," Shields said. "I know that's what they are used to, all these clout chasers out there. I'm like, the real deal. Anything I say I can do, I put my best foot forward and I do it. I haven't lost a fight since I was 17 years old, and I'm 25. I had 77 wins as an amatuer, one loss. I'm 10-0 as a pro.

"I'm not coming to MMA to lose. The next time they see me in the cage, I'm gonna have muscles coming out my damn neck training so hard to win."