The game hadn't even started and Pep Guardiola was giving out tactical instructions.
Shortly after both sets of players lined up for a wonderfully observed minute's applause for Pele at Stamford Bridge, the Manchester City manager - perhaps having noted where Chelsea's players were stationed for kick-off - called Kyle Walker over for a chat.
Walker has probably experienced such moments before, he's played under Guardiola for long enough now after all, but it was a snapshot into just how focused the City boss was on this evening that his side could gain a leg up in their pursuit of Arsenal.
