Close to a decade ago, Sergiy Stakhovsky, a Ukrainian tennis player, won possibly one of the biggest games in his career, when he defeated Roger Federer, knocking him out of the Wimbledon in 2013 in the second round.
But after Russia invaded Ukraine, Stakhovsky is patrolling the Maidan Square, symbol of his country’s "fight for democracy", armed with a Kalashnikov, a pistol in his belt and his 1.93 metre frame dressed in khaki camouflage.
"I cannot say that I feel comfortable around a rifle. I am not sure how I am going to react to shooting at somebody," he was quoted as saying by AFP. "I wish I would never have to be preoccupied with these things."
"I knew I had to go there", he said.
Stakhovsky had called time on his career after the Australian Open earlier this year and was on vacation in Dubai with his family. On seeing the news of the attack on Ukraine, he was plunged into a mixture of "despair" and "misery".
"I was full of adrenaline, I slept three or four hours (overall), I didn't eat".
"My wife was really upset, I mean, she knew, she understood but she was really upset," he said. But "now she understands that I couldn't really do it other way".
Like all Ukrainian men aged 18 to 60, Stakhovsky is eligible for call-up by the army and cannot leave the country when the country is at war.
He now carries out two patrols every day for a couple of hours each, guarding the centre of Kyiv from infiltrations, particularly around the palace of President Volodymyr Zelensky.
Tennis legends from across the globe have offered support, including the man he stunned at Wimbledon, Roger Federer himself.
"He said that he wishes that there will be peace soon," said the Ukranian, adding that Federer and his wife were trying to help Ukranian children through their foundation.
And one message of support that particularly touched him came from Novak Djokovic.
"He lived through this when he was young so he knows exactly what our kids are going through. So from him that message is, I would say, more heavy in terms of meaning."
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