Manchester City have been told they have a potential ‘masterpiece’ on their hands following the 4-2 pre-season victory over Chelsea. City rounded off their US tour in style, beating Premier League rivals Chelsea in front of 71,000 fans in Colombus Ohio. Erling Haaland hit a hat-trick and Oscar Bobb also got in on the act. Pep Guardiola did not have many of his key stars for the tour. But this allowed him the opportunity to give minutes to some of the young academy talents – and several have seriously impressed. Guardiola has confirmed that James McAtee and Nico O’Reilly will now be promoted to…