Heavyweight champion Oleksandr Usyk pictured holding rifle after joining Ukraine defence forces to fight Russia invasion

Heavyweight world champion Oleksandr Usyk has joined Ukraine’s territorial defence forces to defend his country against the Russian invasion.

Reigning IBF, WBO and WBA champion Usyk left London last week to return to his homeland, pleading with Russian president Vladimir Putin to put a halt to the invasion in a passionate message shared on social media.

The 35-year-old has now taken up arms with TSN reporting the champion has joined the Kyiv Territorial Defense.

Andriy Nebytov, head of the national police in Kyiv, shared an image of Usyk dressed in military attire and carrying an assault rifle alongside the message: ‘United for one purpose – to protect our homeland. To victory!’

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Usyk, a 2012 Olympic gold medallist, won every title available in boxing’s cruiserweight division before moving up to the heavyweight ranks in 2019.

Last September, he travelled to London and dominated Anthony Joshua to win his latest world titles. A rematch between the two is expected to take place later this year.

Some of Ukrainian boxing’s biggest names past and present have made efforts to step up and defend their country over the last week.

Former heavyweight champion Vitali, the major of Kyiv, and brother Wladimir Klitschko have both vowed to take up arms amid the conflict.

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Vasily Lomachenko meanwhile has joined the ‘territorial defense battalion’ for his hometown of Bilhorod-Dnistrovskyi, which is located in the south