Hey Nic, I watched this clip sometime last year. I couldn’t believe it either so did some searching and discovered how it was made. Can’t find the url anywhere afraid. A man dressed in one of those neon blue suites, that can be erased easily in a video editing program, was following the footballer around with a ball on the end of a long stick. Using perspective very smartly and some sound editing they created the goal post shots.

And now you know