Yet surely there's no other joy like getting up close and taking a selfie with a quokka, the ultra-cute marsupial that's native to Australia's Rottnest Island.
The 36-year-old player did just that on Thursday, helping to promote his appearance at the Hopman Cup tournament in Perth by taking a few happy snaps with the adorable animal.
"I thought it was a like a bigger mouse, but it's more like a smaller kangaroo. They're very cute," Federer said.* Read more...