That's Using Your Head

Blonde Jessica Kastrop was the ultimate professional as a stray kick struck her at more than 100mph during a pre-match warm up.
Footage of her unfortunate header has since become a YouTube sensation.The German's head was sent plunging forward with the massive impact but incredibly she bounced right back.

The ball had been kicked by former Chelsea star Khalid Boulahrouz who dispatched a long-range effort during practice ahead of a Bundesliga pre-season clash in Stuttgart.

It hit her with such force her knees buckled and she had to brace herself against a lectern to stop herself collapsing in a heap.
Jessica said afterwards: "I was fine - eventually. Boulahrouz ran over to me straight away and apologised."

Via

The funniest part of this..? The "THUD" that's clearly audible.