6:53 PM ET

As the country tries to fend off an invasion from Russia, the No. 8 pound-for-pound boxer has joined a territorial defense battalion.

The two-time Olympic gold medalist is shown in military fatigues in an image posted on the official brand that he shares with Oleksandr Usyk. The man traveled to Greece to be with his family, but returned to his home in the evening.

A June 5 fight in Australia between undisputed lightweight champion George Kambosos and former three-division champ Vasyl Lomachenko would be televised in the United States on June 4. The sides of the deal were agreed to earlier this month.

After suffering a decision loss to Teofimo Lopez in October of 2020, he underwent surgery to repair a torn rotator cuff. He defeated Richard Commey in December.

The mayor of the capital of Ukraine, Vitali Klitschko, said he was going to defend himself. His brother, Wladimir, a former world champion, enlisted in the reserve army in anticipation of the invasion.

"We are proud of our boxers, our real champion in boxing and our champion in this war," said Kovalchuk.