Kate Martinez wins in Japan, Kate Martinez mma

In 2010, Kate Martinez was selected to represent the United States at the 2010 Girls S-Cup World Tournament in Japan. The S-Cup Tournament showcases SHOOTBOXING, which is a kickboxing sport that incorporates judo throws and standing submissions. The official SHOOTBOXING organization headquarters is located in Tokyo, Japan. Kate was selected based on her kickboxing background, Jiu-Jitsu lineage, and history of winning MMA fights with standing submissions.

In the first round of the tournament, Kate Martinez faced Thailands Champion, ZaZa Sor Aree, a  Muay Thai Champion with an extensive fight record. Kate had a dominating performance, and in the third round she secured a head and arm choke that put Zaza to sleep. Kate Martinez became the first woman to win an S-Cup match via standing submission.

After advancing to the semi-finals, Kate Martinez faced the reining S-Cup Champion RENA, whom in 2010 was ranked as the #1 female kickboxer in Japan. Kate and RENA had a three-round war, but in the end Kate fell short on points and lost the decision. The fight was a loss on her record, but the experience was nonetheless cherished. "Getting the opportunity to go toe-to-toe against the best kickboxer in Japan was the greatest experience of my fight career."