Five things we learnt at Stamford Bridge during Chelsea's remarkable 4-1 victory over Napoli Harry Redknapp's side were thrilling on the counter-attack and took the game to teams no matter their reputation. Defending was a bit of an afterthought. Napoli are worthy heirs. They beat Cagliari 6-3 in their last league game and looked exactly that tonight: a team that can score six with ease but ship three just as quickly. Napoli were brilliant going forward at the Bridge but conceded chance after chance to Chelsea when the pressure was on. Catenaccio clearly did not catch on in Naples. 3 Chelsea were hardly less chaotic at the back In Jose Mourinho's first two seasons, Chelsea conceded just four goals in 12 Champions League group games and developed an imposing aura on European nights. Think of the 2009 semi-final against Barcelona under Guus Hiddink, when they drew 0-0 at the Nou Camp and were only beaten by a late Andres Iniesta goal at the Bridge. Last night they traded blows with Napoli but the Italian side tore them apart on the counter time and again. Too often it was too stretched and too scrappy and a side as good going forward as Napoli will not let you get away with that. 4 Michael Essien is having to reinvent himself The Ghanaian's career has been brutally damaged by knee injuries and he clearly cannot impose himself physically like he did in the past. How many times did Essian cover every blade of grass on nights like this? Essien is still getting his match sharpness back from his latest injury but at 29 he clearly cannot storm around the pitch like his former self. He did not seem to know what to do with himself in the first half but in the second he played with discipline and tactical intelligence - perhaps he can become the holding midfielder Chelsea have needed since Claude Makelele left the club. 5 What an underrated player Branislav Ivanovic is. The Serb is never at the centre of attention but always at the heart of the action. He does not do controversy, does not do mutiny, and in these big games he is always whole-heartedly committed, filling in at full-back or centre-back, wherever he is needed. His header won the penalty for the crucial third goal before he claimed what proved to be the winner himself. But it was his tireless work up and down the right flank that helped more than anything rein in the Napoli attacks as the game wore on.