A hat-trick from Nicolas Jackson helped Chelsea manager Mauricio Pochettino enjoy a successful return to Tottenham, but only after a pulsating contest with two red cards and five disallowed goals.Chelsea's 4-1 victory ended Spurs’ unbeaten start to the Premier League season and earned Pochettino the first statement result of his reign – but it only told half the story.Dejan Kulusevski fired Ange Postecoglou’s team in front during a 57-minute first half, where Cristian Romero earned a straight red card and Cole Palmer netted from the resulting penalty.Tottenham also lost Micky van de Ven and James Maddison to injuries, while three goals were disallowed with video assistant referee John Brooks a busy man.Spurs were reduced to nine men soon after half-time when Destiny Udogie was dismissed and the visitors’ numerical advantage finally told when Jackson slotted home in the 75th minute before he completed his treble with two stoppage-time strikes to bring an action-packed London derby to an end.While all the pre-match focus centred on the reception Pochettino would get from the home fans, he walked out with the PA system booming so his main greeting turned out to be a bear hug from opposite number Postecoglou.This match rarely disappoints for drama and Moises Caicedo’s crunching third-minute tackle on Maddison set the tone.The rivalry between the clubs had always been there, but it ramped up a notch during Pochettino’s Tottenham tenure and especially after the 'Battle of the Bridge’ in 2016.Almost four years to the day since his sacking, this was Pochettino’s first return to N17 and he watched his new team concede after only six minutes.Maddison was behind it with a wonderful pass under pressure into Pape Sarr, who recycled