I written a few takes of smaller competitors defeating larger competitors in full contact sports. The difference now is that it will focus on smaller female competitors defeating larger female competitors.
1.) Reina Miura vs Jazzy Gabert: In this fight the smaller competitor(Miura) easily defeated the much larger competitor(Gabert). Miura is only 5’3” and weighs 164 lbs yet she managed to defeat the 6’1” 195lb power lifter and strongwoman Jazzy Gabert by submission.https://www.mma-core.com/videos/King_Reina_vs_Jazzy_Bagert_RIZIN_5_Full_Fight_Part_2/10172639
2.)Reina Miura vs Lei’D Tapa: Reina Miura has proven herself to be a giant slayer. Miura who’s only 5’3” and weighs 164lbs defeated the 5’11” 193lb Lei’D Tapa https://www.mma-core.com/videos/Reina_Miura_vs_Lei_D_Tapa_Full_Fight_Rizin_WGP_2017_Part_2/10186799 
3.)Reina Miura vs Kristen Handel: Reina Miura also defeated the 6’0” 165 lb Kristin Handel by tko. Reina dominated her much larger opponent. They did trade blows at first but the fight concluded on the floor with Reina mounting Kristen.
4.)Ann Wolfe vs Vonda Ward: As saying goes “the bigger they are, the harder they fall”. Ann Wolfe who stands 5’9” knocked out the 6’6” Vonda Ward. Vonda was undefeated prior to this fight. Ann gave Vonda her first and only loss.
5.) Reina Miura vs Crystal Stokes: She’s back. Reina Miura once again showed her giant slaying skills by defeating the 6’0” Crystal Stokes by decision. Reina Miura dominated the much larger Crystal early in the fight and nearly locked on a armbar on crystal but the round ended, possibly saving crystal from losing by submission. Crystal did manage to launch some offense on the second round but it wasn’t enough to stop Miura who landed several well placed strikes on Crystal on the third round which allowed Miura to win the bout by decision. Despite it being Crystal’s first MMA bout, she was still Reina’s toughest opponent. Crystal is a Brazilian Jiu Jitsu gold medalist, a former US marine and a professional football player that does strongman training.
6.) All of Gabi Garcia’s losses: Gabi Garcia(pictured below) is perhaps the most physically imposing female martial artist there is. She stands 6’2” and currently weighs around 230lbs. However during her days as a BJJ competitor she weighed around 245lbs. She has a record of 58 wins and only around 8 losses. Her first losses happened between 2007 and 2008, when when she lost to the much smaller Luciana Dias. Luciana beat her on 3 occasions, 2 of those occasions where by submission. Another woman who beat her was Hillary Williams who despite being smaller than Gabi, managed to throw the much larger Gabi by performing the Ippon seo nagi. Ana Carol Vidal who is only 5’2” and weighs 125 managed to defeat the much larger Gabi Garcia. Lana Stefanic beat gabi as well. One of her most notable losses was against Ana Laura Cordeiro . Despite Ana being dwarfed by Gabi she still managed to win by decision. The most impressive bout was between Jessica Oliveira and Gabi Garcia, what made that bout impressive was that not only did the smaller Jessica Oliveira(Flowers) win by decision but that she also had a lower belt rank than Gabi. Mackenzie Dern who is around 5’2” and weighs around 120 also managed to defeat her by using defense and by penalties.
8.)Mackenzie Dern vs Talita Nogiuera: The name Mackenzie Dern is a well known name in the sport of Brazilian Jiu Jitsu. The saying “Tiny but mighty” perfectly describes her. She’s only 5’3” and alternates between 120-139lbs. Yet she is one of the most highly decorated bjj athlete. She has 75 wins and 25 losses. Many of her wins were against larger opponents. One of those wins was against the 5’10” 145lb Talita Nogiuera.
9.) Mackenzie Dern vs venla Luukkonen: Mackenzie used her fluidity advantage to 
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