On July 16, 2016 Nobuyuki Sakakibara announced at a press conference that Rizin Fighting Federation will host a 16-man openweight tournament September 25 in Tokyo.
This tournament was included Pride FC veterans like Kazuyuki Fujita, Tsuyoshi Kosaka, Heath Herring, Sumo sensation Baruto Kaito, world class wrestler Amir Aliakbari, and Rizin GP 2015 winner King Mo Cro Cop won the championship.
Background Jiří Procházka was injured and couldn't participate in the second round of the Grand Prix, and was subsequently replaced by Tsuyoshi Kohsaka.
Mirko Cro Cop was originally scheduled to have a rematch with Wanderlei Silva in the Openweight Grand-Prix Quarter-Finals.
Shinobu Kandori was originally set to take on Gabi Garcia, but was replaced by Yumiko Hotta after suffering a rib injury.