There was a moment during a break in a recent training session when Jose Mourinho was busy explaining to Ander Herrera some of the specifics he wanted from the Manchester United midfielder. A voracious learner, Herrera was taking it in all but it was when Mourinho had stopped talking that the Spaniard explained to his manager that what he was requesting was virtually the opposite of what he had been told to do over the previous two years by Louis van Gaal. That was not Herrera having a dig at Van Gaal as such – a consummate professional, he has never been one to snipe, no matter his frustrations – but it provided Mourinho with another reminder of the challenge he faces undoing much of his predecessor’s work. It also told him that, in Herrera, he has a player eager to embrace his methods, someone desperate to escape the suffocating straight-jacket of Van Gaal’s tactics and get back to playing to his strengths, to start enjoying his football again.