Ukrainian Tennis Star Sergiy Stakhovsky on Trading in Racket to Fight on Front Lines for His Country

SERGEI SUPINSKY/AFP via Getty Images Sergiy Stakhovsky

In just two months, Ukrainian tennis star Sergiy Stakhovsky has gone from the courts at the Australian Open to patrolling the streets of Kyiv armed.

Yet the one-time men's world No. 31 has no regrets about joining his countrymen to fight amid Russia's invasion of Ukraine, even though it meant leaving his wife and three children behind in Budapest, Hungary.

"We were in Dubai having a vacation," Stakhovsky, 36, tells PEOPLE by video from his base in the Ukrainian capital. "It ended just four days before the invasion. So, we flew back to Budapest, I put them home, and then I drove myself to the border and got myself to Kyiv."

Stakhovsky still says the entire experience since then has been surreal.

"Never in my life would I expect to walk the streets of Kyiv with a gun in my arm," says Stakhovsky. "But when you see on a daily basis what the Russians are doing to civilians and innocent people and kids, the amount of anger is sometimes insane."

Guillaume Horcajuelo/EPA-EFE/Shutterstock Sergiy Stakhovsky on court

Continues the former athlete, "We have seen people shot in the back while they are trying to leave their homes, just because they had no more supplies left. I saw a father who lost his entire family. He was trying to come back for them — they were trying to escape."

All has been a far cry from Stakhovsky's 16-year career on the pro tennis circuit. Having walked away from the sport after falling out of the Australian Open in January, Stakhovsky expected to now be enjoying the lazy days of retirement at his vineyard in western Ukraine and developing a national sporting program for Olympic athletes ahead of the 2024 Paris Games — a project he was due to launch on March 3 with Ukrainian President Volodymyr Zelenskyy.

Presidency of Ukraine/Handout/Anadolu Agency/Getty Ukrainian President Volodymyr Zelenskyy

Tragically, like millions of his fellow countrymen and women, the Russian invasion has put all these plans on hold. Along with fellow sports stars Vitali and Wladimir Klitschko, and prizefighters Vasiliy Lomachenko and Oleksandr Usyk, he now spends his days doing all he can to defeat the Russian invasion.

While he says that Kyiv itself is relatively calm at the moment compared to other regions of Ukraine, this means coming face-to-face with the harsh realities of life under invasion as a steady stream of refugees travel through the country's capital in search of transport to the safety of the west.

"It's really tough," he says. "These people left their homes with nothing. They lost their houses and cars and everything they had. And at the best they are all together as a family — you know, they have nothing but at least they are all alive. At worst they have lost some of their family members and they are still going into the unknown in the west of Ukraine and then onwards to Poland, Slovakia, Hungary, England."

"People are also coming back," he continues. "There's more traffic and more people in Kyiv. But this is unfortunate because it is predominantly people who left but didn't have the financial resources to stay away for long. Once they have drained all their savings, they come back to Kyiv because it's the only place they have. They are putting themselves in great danger."

As for the future, Stakhovsky is assured that Ukraine will not be defeated because its people "will never give up their freedom."

"That's why in every city, in every village they are fighting brave," he tells PEOPLE.

He's also appreciative of the support that the rest of the world has given to the Ukrainian people, which, in his case, has included kind messages from American tennis pros Andy Roddick and Mardy Fish.

His main priority, however, is to do his duty for his country and help make the people of Kyiv feel safer. After that, he will return to the only thing that's more important: his family.

"Kyiv is my city. I was born here. My grandparents are buried here and my great-grandparents," says Stakhovsky. "On the other hand, I have three kids and the oldest one in a week's time is going to be eight and the youngest is going to be three. I should be there with them, and I feel guilty while being here that I left them."

"But Russians are killing and shelling civilians," he continues. "There's not one structure in Mariupol city which is not touched by the destruction. So, there was no win for me. Here [in Kyiv], I am just trying to do as much as I can, so I don't feel guilty that I am spending my time here.

"I hope that one day I can go back to my family. That is the most important thing."

The Russian attack on Ukraine is an evolving story, with information changing quickly. Follow PEOPLE's complete coverage of the war here, including stories from citizens on the ground and ways to help.