Time moves fast in football. In the short term, it's remarkable that we're already preparing for this weekend's Community Shield fixture at Wembley, just three weeks after France were holding the World Cup trophy aloft in Moscow. In the longer term, it's incredible that Pep Guardiola is now a decade into his managerial career.
Other revolutionary managers find themselves washed up 10 years after their "defining" campaign, as Guardiola's 2008-09 season should probably still be considered. Either they've become weighed down by the stress of football management, like Arrigo Sacchi, or they've discovered their methods have been replicated and improved upon, like Arsene Wenger found.