It was the Paris-born winger who netted twice before PSG had Angel Di Maria sent off. City won 2-0 to eliminate last season’s finalists 4-1 on aggregate on Tuesday.
The champions will go into the game as favourites though, on the back of their remarkable record against 'Les Dogues'.
Mbappe also (22 years, 80 days) becomes the youngest player in history to score 25 Champions League goals, taking the record from Messi (22 years, 286 days).
Kylian Mbappe's hat-trick powered Paris Saint Germain (PSG) to a 4-1 win over Barcelona in the first leg of their Champions League last-16 tie here on Wednesday.
PSG moved three points clear of second-place Lille, which can move level on points by winning at fifth-place Rennes on Sunday but has a vastly inferior goal difference.
PSG announced on its website that former Tottenham manager Pochettino had signed a contract until June 30, 2022 with an option for an additional year.
Brazilian striker missed PSG's last game, a 2-0 win over Lorient in Ligue 1.
The score was 0-0 when the incident took place about 14 minutes into the match.
Buffon, who played a record 176 times for Italy, has an option to extend his stay at the Parc des Princes for a further season.
UEFA announced in June that the probe opened last September had closed and while PSG escaped sanctions, the club remained under scrutiny.
The 29-year-old midfielder Javier Pastore signed a five-year contract with AS Roma that runs until June 30, 2023.
Tuchel was unveiled to the media at the Parc des Princes on Sunday evening, after his appointment on a two-year deal was confirmed last week.
The world's most expensive player might not feature for his club again this season, with the doctor who will operate on his fractured foot in Brazil saying he could be out for three months.
The world's most expensive player, 26, arrived on an Air France flight from Paris and left in a wheelchair, a photo taken by one of his fellow passengers showed.
Neymar, the world's most expensive footballer, was stretchered off 10 minutes from time at the Parc des Princes as PSG opened up a 14-point lead in Ligue 1.