Sergiy Stakhovsky will join the Ukrainian reserve army to fight for his country. Stakhovsky was once ranked as hig as world number 31 and defeated Roger Federer at Wimbledon in 2013. He retired from tennis after the Australian Open early this year.

Stakhovsky will leave his wife and children in Hungary while he joins the army. Speaking of decision to join the reserve army, Stakhovsky said:

I know how to use the gun, I pretty much hope that I will not have to use the gun, but if I have to, I’ll have to.

While several tennis players have posted ant-war messages on social media, Stakhovsky is the first well-known tennis player to join the army to fight the Russian invasion.

Stakhovsky said that he received messages of support from Novak Djokovic but Roger Federer and Rafael Nadal haven’t responded to his messages.