Kazuto Ioka (26-2) cemented his legacy on New Year's Eve, stopping unbeaten three-division champion Kosei Tanaka (15-1) in eight rounds to retain his WBO super flyweight title.  The bout served as a TBS main event in Japan on date that is traditionally reserved for the biggest fights in the country.

Many experts believed that the younger and fresher 25-year-old Tanaka would be too much for Ioka but the 31-year-old's moxie and intelligence proved to be the difference in the fight.

"The reality of this fight is that Tanaka is a young, hungry fighter but he had never fought anyone of the caliber of Ioka and when you have two great fighters meet in the ring - usually the experienced fighter emerges victorious and that is exactly what happened," Ioka's trainer, Ismael Salas, told BoxingScene.com.

In a recent article published on BoxingScene.com, Salas revealed that the end is nearing for Ioka and that he may call it a career in the near future.

After conquering four divisions, there isn't much left for Ioka to achieve. 

However, Salas did say that making a run at five division titles is intriguing to the Japanese fighter and mentioned a current pound-for-pound great as a potential target.

"That is what we are analyzing. He confessed to me that he doesn't want to stay (in the sport) much longer but he is interested in moving up to 118 pounds where he can make history as a five-division champion. So far these are only conversations and nothing is concrete," said Salas.

"After the fight he said that he doesn't want to fight in Japan anymore and that he wants to finish his career by fighting in the United States.  There are several big fights that can be made at 115 and 118 pounds including a showdown against Naoya Inoue which I think would interest the fans."

Inoue, who is a three-division champion, currently holds the IBF and WBA bantamweight titles and is regarded by most experts as one of the top three fighters in the world. 

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