'Sorry about the hat': Celebrities and athletes respond to Roger Federer's challenge

Celebrities, rivals and sport stars have responded to Roger Federer’s crazy ‘training at home’ challenge that gripped fans worldwide in self-isolation due to the coronavirus pandemic.

Like the rest of his fellow tennis professionals, the Swiss maestro is stuck in isolation with tennis tournaments cancelled until mid-July at the earliest.

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As part of his social media messaging, the 20-time Grand Slam champ has been showing off different ways he has been keeping healthy during isolation.

In his latest video, Federer donned a hat he bought from Ecuador and showcased his tennis skills up close against the wall.

In a similar approach to Australian cricket great Don Bradman throwing a golf ball at a wall and hitting it back, Federer encouraged fans to give his method a crack.

The 38-year-old also urged viewers to "choose their hat wisely".

The video prompted a craze on Twitter with thousands sending their videos in and Federer responding with admiration to many.

Hugh Jackman and Novak Djokovic respond

But Federer also challenged a host of celebrities to show off their regime.

Some of them included Rafael Nadal and Novak Djokovic, Footballer Cristiano Ronaldo, actors Hugh Jackman and former WWF star Dwayne ‘The Rock’ Johnson and survivor specialist Bear Grylls.

And a few have started to respond to the #trainingfromhome challenge.

Aussie actor Jackman responded to the video claiming while he doesn’t have a tennis court at his place in New York, he does have plenty of stairs to run up.

Real Madrid star and World Cup winner Toni Kroos decided to take on the challenge directly.

Although he apologised for his choice of bucket hat, which didn’t quite compare to Federer’s style.

Opponent Novak Djokovic also asked Federer if his technique against the wall was “good enough?”

To which Federer cheekily reminded him: “You’ve beaten me with that volley more than a few times, I don’t think you need any tips.”

Former US tennis ace Andy Roddick responded saying he was never a fan of volleying.

Many fans are waiting for the response and banter back and forth from friend Nadal, basketballers LeBron James and Steph Curry, NFL great Tom Brady and the adventurous Grylls.