The bout we're talking about happened 8 months before the Inoue bout and saw Hernandez fighting against Atsushi Kakutani, a fighter all but unknown outside of Japan.
Inside a minute of the fight Kakutani had dropped Hernandez on the seat of his pants. Unfortunately for Kakutani that was his major moment of success as Hernandez found his groove soon afterwards and slowly, but surely, ground down the Japanese challenger who was stopped in round 4 after some great action between the two men.
Despite the loss here Kakutani did actually play a part in Inoue's win over Hernandez and sparred with Inoue ahead of his bout with Hernandez. Not only did the two spar but Kakutani also informed Inoue's team that Hernandez wasn't as tall as he had been reported to be. Something that certainly helped Inoue prepare for the Mexican.
(Video courtesy of