If you're a Manchester United fan - you will understand (they just got HAMMERED by a lowly team called MK Dons)!!!!
No, never heard of them
They used to be Wimbledon FC, of Vinnie Jones and John Fashanu fame. The club gained their only bit of interest (or notoriety) by actually moving to another city (Milton Keynes) and changing their name, in a similar way to NFL clubs relocating. As a result they earned a nickname (Franchise) and the contempt of every other club in the Football League for uprooting a communal hub, which is what football teams are, after all.
Well, their only bit of interest until now, of course.