No pun intended. I really liked the idea and the pair of main characters really have a good chemistry together (one could argue their friendship is what holds it all together). The actors do a decent job. So what do I think went wrong? And I'm not talking about the actual plan (if you want to call it that).
Well I'd say that the pace but especially the intentions are a bit muddy to say the least. It also changes far too often (mood swings), has logical errors and if you're not interested in football (or soccer if you're American), than this will leave you cold. The basic idea also could be described as a bit mental. Then again, if you are into the world of fandom, you might understand at least part of it. Still it could've been better, even though it has quite a few nice moments in it (though a character falling down twice is at least one too many)