Formations don't win football matches apparently. But they can start feuds. In 2011 Antonio Conte infuriated Walter Mazzarri with a tactical tweak when his Juventus travelled south to take on Napoli. Now their frosty relationship is on our shores as Watford meet Chelsea this weekend.
The two Italians are very different characters, despite sharing an intense hunger to win. Tuscan Mazzarri can seem standoffish and cold, but is known to form a fierce paternal bond with his players. It's just that the cameras don't see his warm, nurturing side. 'I treat my players like my sons,' he once said.