Unbeaten Mayweather captured world titles in five different weight divisions and was considered the best pound-for-pound boxer in the sport Rules were not specified as of yet TOKYO: Boxing superstar Floyd Mayweather Jr said Monday he will come out of retirement to fight Japanese kickboxer Tenshin Nasukawa on New Year’s Eve in Saitama, north of Tokyo. The 41-year-old unbeaten American, who captured world titles in five different weight divisions and was considered the best pound-for-pound boxer in the sport, beat Irish mixed martial arts fighter Conor McGregor in his last fight in August 2017. That victory improved his boxing record to a perfect 50-0 but the format or rules for his meeting with Nasukawa were not specified by the Japanese promoters. Mayweather posted a teaser photo on his Instagram feed at the weekend, showing him wearing kickboxing gloves.