April 8, 2020 1:15 PM EDT

While Wimbledon was cancelled this year because of the coronavirus, it looks like tennis star Roger Federer is staying in shape and has gotten more people to join him.

While tennis is best and traditionally played with at least one partner, the champion shows that it can be a demanding solo game too. At this time of social distancing, the star has issued a challenge for anyone trying to work out alone.

Federer took to Twitter to show off his backboard skills, standing inches from the wall and hitting forehand volleys, all while wearing a dapper fedora. “Here’s a helpful solo drill. Let’s see what you got!” he wrote on Twitter. “Choose your hat wisely,” he also suggested.

A number of tennis players from around the world replied, and hoped for some tips from the star. And they took their swings while wearing hats, of course.

Federer responded to some of the many folks joining him in his #TrainingFromHome challenge, offering encouragement.

Federer also used the social site to nominate other stars, athletes, and notable personalities to take part in the challenge, including his on-court rival Rafael Nadal, football star Tom Brady, Dwayne Johnson, Bill Gates, The Daily Show host Trevor Noah, Man vs. Wild star Bear Grylls, and Coco Gauff.

So far, the challenge has been accepted by stars from around the world including soccer star Toni Kroos and actor Hugh Jackman.

U.S. tennis player Andy Roddick responded with his own inside joke for tennis fans, saying he would take part in the challenge, but he doesn’t “like to volley.”

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