LONDON, Sept 23 (Reuters) - Chinese heavyweight Zhilei 'Big Bang' Zhang knocked out Britain's Joe Joyce in the third round of their rematch at London's Wembley Arena on Saturday. The 40-year-old Zhang sent his 38-year-old opponent sprawling to the canvas with a huge right hook to his jaw. Joyce got back to his feet and received oxygen after the referee waved off the fight. Zhang, the 2008 Olympic silver medallist who stopped Joyce in six rounds last April at London's Copper Box, is the WBO's mandatory challenger for Ukraine's WBO, IBO, IBF and WBA champion Oleksandr Usyk. Britain's 'Gypsy King' Fury is the holder of the WBC world heavyweight belt.

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Persons: Zhang, Britain's Joe Joyce, Joyce, Oleksandr Usyk, it's, Tyson Fury, Fury, Alan Baldwin, Ken Ferris Organizations: London's Wembley, Ukraine's WBO, IBO, IBF, WBA, WBC, Thomson