Naoya Inoue retains undisputed title after TJ Doheny quits with injury

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Japanese boxing superstar Naoya Inoue remained the undisputed world super-bantamweight champion when Irish challenger TJ Doheny dropped to his knee and quit in the seventh round because of an apparent back injury on Tuesday.

Doheny complained of a twinge" after walking back to his corner gingerly. Before then, he was getting pummeled by Inoue, who celebrated his technical knockout - for a 28th successive win - in muted fashion in Tokyo.