MMA Fighting Share this story Photo by Edward Diller/Getty Images Boxing champion and Olympic gold medalist Claressa Shields has officially booked her first fight in mixed martial arts as she squares off against Brittney Elkin as part of the upcoming PFL card on June 10. Promotion officials announced the news on Wednesday. Shields’ debut will take place as part of the card that will also kick off the second half of the upcoming season airing on ESPN2. “I am very excited to cement my legacy as the greatest woman of all time,” Shields said in a statement. “I cannot wait to step into the PFL cage for the first time on June 10 and show the world that I never back down from a challenge. I have shown I am the best boxer in the world and eventually I intend to do the same thing as a mixed martial artist.”