PSG went ahead courtesy of a Marquinhos header in the first half, but Mauricio Pochettino's side lost control after the break with De Bruyne and Mahrez finding the back of the net in the space of eight minutes to secure City's 18th consecutive away win in all competitions.
Last year's runners-up PSG then found themselves with a higher mountain to climb as Idrissa Gueye picked up a straight red card in the 77th minute for a reckless challenge on Ilkay Gundogan.
