Don't try this at home, kids!
On Saturday, Elina Svitolina posted a blooper of fiancé Gaël Monfils standing in the firing line of the couple's friend, Roger Federer, at the back of a practice court.
“I know it’s a big challenge for you, but try to relax your arm and you can do it," Svitolina said in the clip.
Federer proceeded to hit three tennis balls in succession in the direction of the Frenchman...