Heavyweight warriors: Boxing legends Vitali and Wladimir Klitschko 'ready to fight' Russia

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Wladimir Klitschko, who holds the record for the second-longest reign as a heavyweight champion in boxing history, recently joined Ukraine's reserve army. He also declared he would fight for Ukraine in a message posted on LinkedIn on Thursday, and urged others to do the same.

Wladimir wrote, "Democracy cannot defend itself; it needs the will of the citizens, the commitment of everyone. Basically, there is no democracy without democrats. Here, we will defend ourselves with all our might and fight for freedom and democracy. You can also act. Let not fear seize us; let's not remain frozen."

The 45-year-old then urged world leaders to impose swift and severe sanctions against Russia and said, "This war against my country is not only the result of one man's madness, but also the result of years of weakness in Western democracies. This madness must be stopped now by stepping up deterrents. Our governments need to say things loud and clear."

In a joint video, the two brothers called for international support for the Ukrainian cause.

The Klitschko brothers aren't the only professional boxers in Ukraine who have been impacted by Russia's invasion. According to MARCA, Vasiliy Lomachenko, a two-time Olympic gold winner and three-division champion, escaped Ukraine for Greece. Oleksandr Usyk, the WBA, WBO, and IBF heavyweight champion, who fought Anthony Joshua in September, was in London this week for a video game advertising event before returning to Ukraine on Thursday.

In an Instagram video, Usyk stated, "Some wrote to me that I ran away; I didn't, I was at work but I'm back, I'm home. Friends, we have to unite because it's a hard time right now and I'm really emotional and worry about my country, and our people. Friends, we have to stop this war; all of us together."