The PFL 4 mixed martial arts event for the 2021 season of the Professional Fighters League was held on June 10, 2021. This was the fourth regular season event of the tournament and included fights in the Featherweight and Lightweight divisions. Boxing champion and Olympic gold medalist Claressa Shields made her MMA debut in the main event against Brittney Elkin.

The PFL 9 mixed martial arts event for the 2021 season of the Professional Fighters League was held on August 27, 2021. This was the third event of the playoffs with the Featherweight and Light Heavyweight divisions divisions competing. This event aired on ESPN2, with the prelims airing on ESPN+.

UFC Fight Night 156: Shevchenko vs. Carmouche 2 was a mixed martial arts event produced by the Ultimate Fighting Championship that took place on August 10, 2019 at Antel Arena in Montevideo, Uruguay. A UFC Women's Flyweight Championship bout between current champion Valentina Shevchenko and former UFC Women's Bantamweight Championship challenger Liz Carmouche headlined the event. The pairing met previously under a regional promotion banner in 2010 with Carmouche winning the first bout via second-round TKO (doctor stoppage).

UFC Fight Night 148: Thompson vs. Pettis was a mixed martial arts event produced by the Ultimate Fighting Championship that was held on March 23, 2019 at Bridgestone Arena in Nashville, Tennessee. A welterweight bout between former two-time title challenger Stephen Thompson and former WEC and UFC Lightweight Champion Anthony Pettis served as the event headliner.

UFC Fight Night 139: Korean Zombie vs Rodriguez was a mixed martial arts event produced by the Ultimate Fighting Championship that was held on November 10, 2018 at Pepsi Center in Denver, Colorado, United States. A featherweight bout between former UFC Featherweight Championship challenger Chan Sung Jung and Yair Rodríguez served as the event headliner.