Miura actually began his fighting career way back when and made his professional as an MMA fighter back in 2004, fighting in a Pancrase tournement. By the time of his boxing debut in 2009 he had gone 9-6 in MMA fighting for Pancrase, K1 and WEC, where he fought Carlos Condit for a title. It was due to his boxing training whilst fighting as an MMA fighter than he actually turned to boxing and earned his OPBF title fight.
Last year Miura turned back to MMA and scored a pair of wins in Pancrase and was supposed to fight again earlier this year, however that bout failed to take place. According to the Japanese press he is now booked for a Pancrase title fight on Pancrase 281, against Akihiro Murayama. The bout, which isn't yet listed on the brilliant MMA website Sherdog.com has been noted by several reliable Japanese sources, and is set for OCtober 2nd at the Differ Ariake Coliseum.