The Man. United v. Arsenal rivalry that dominated the early 2000s wasn't so much the fans hating each other, but the players. And by hated each other, we mean fucking despised one another. (More on this later.) In 2003, after United striker Ruud van Nistelrooy had played a part in getting Patrick Vieira sent off, he then missed a last-minute penalty. Defender Martin Keown and others couldn't really hide their delight. Keown was later fined £5,000 for taunting and pushing RvN, but we're sure he'll tell you that it was well worth it.