When you're the world number 772 and you're taking on the greatest tennis player the world's ever seen, you need all the help you can get.
And what Marcus Willis' fans are doing to show their support as he takes on Roger Federer is taking off their shoes.
Now, exactly what taking off your shoes does to help the underdog out isn't entirely clear - apparently it's inspired by one of the Brit's favourite pranks.
But what is clear is that if you're not doing it, you can't call yourself a fan.
And if you're not one for showing your feet to the world, but you still want to get involved, you can always join in with the chant.
You know the one...
Willbomb-mania is truly in full swing.