Wow. Just unthinkable. Manchester City have been famous across the footballing landscape for their unforgiving nature and perversity, but they escalated the same notion to the next dimension by taking a hapless Watford to the cleaners.A hat-trick from Bernardo Silva, accompanied by goals from David Silva, Riyad Mahrez, Sergio Aguero, Nicolas Otamendi and Kevin de Bruyne completed a jaw-dropping rout of a disintegrated Hornets side.After succumbing to a shock defeat at Carrow Road, Manchester City had to respond to keep pace with league leaders Liverpool. Perhaps, they took the motive too seriously. As for Watford, they now have lost 12 consecutive games against the champions.After all the stories, headlines and records created by the Cityzens, Pep Guardiola added another to his elite list of accomplishments at the Etihad, recording his biggest-ever victory in terms of margin in English football.The score, in fact, could have even reached double figures for the hosts. Aguero could have had a hat-trick himself, as he was always buzzing around, wriggling through defenders, getting his shots away and making stellar runs into the six-yard box.One of his efforts clattered the frame of the goal, while Riyad Mahrez too was denied a second of the afternoon.On that note, we aim to list down three of many reasons that led to this irresistible, relentless performance from Manchester City.6 - Manchester City have scored six goals in consecutive games against Watford; this is the first time an English top-flight side has scored 6+ goals in back-to-back meetings in all competitions with another top-flight club since Chelsea v Wigan in 2010. Cricket.— OptaJoe (@OptaJoe) September 21, 2019#3 Correcting their mistakes at the backFernandinho put in a solid shift at the heart of the backlineManchester City committed schoolboy errors in the previous PL game against Norwich, with the centre backs often seen viewing the game at a pedestrian pace.This time around though, Guardiola took no time to muscle Fernandinho into the setup. Rodri kept his place, with the Brazilian occupying the heart of defence alongside Nicolas Otamendi.Fernandinho brought about a sense of calm around the last line. He was apt at everything he did - be it with mopping up danger or sensing it. He won a host of interceptions, read the final ball and chipped in with vital tackles when his side were shorn of a few bodies at the back.He often seems to give his 100%, and once again today, the ever-so-reliable Fernandinho, along with Kyle Walker, the returning Benjamin Mendy and Otamendi, put in a good shift.