Trailing to Marquinhos' header at the break, City turned the contest around through Kevin De Bruyne and Riyad Mahrez.
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Manchester City take a 2-1 advantage into the second leg of this UEFA Champions League semi-final after an impressive comeback success in the French capital.
Match in brief
Mauricio Pochettino's side were quickly out of the blocks with Neymar testing Ederson before Marquinhos towered above the City defence to head in Ángel Di María's 15th-minute corner. Phil Foden was denied by Keylor Navas from the visitors' clearest opening but, on the whole, Paris kept Josep Guardiola's men at arm's length before the interval.
The second half was a different story. City dominated possession and their pressure told when Kevin De Bruyne's cross-shot veered inside the far post, quickly followed by Riyad Mahrez's free-kick zipping through the Paris wall and past Navas.
Any hope of a recovery on the night from the hosts disappeared when Idrissa Gueye was dismissed for a late tackle on De Bruyne.
Player of the Match: Kevin De Bruyne (Manchester City)
"De Bruyne, as always, dictated play with his simple, crisp passing and was a hive of activity in the City midfield."
Patrick Vieira, UEFA Technical Observer
Chris Burke, Paris reporter
Paris suffered their eighth home defeat of the season after letting this game slip from their grasp. Pochettino's side had controlled the first half so well and ought to have scored more than once before being guilty of dropping back and letting City come at them. The result was a dramatic turnaround that leaves them needing another heroic away display to match their wins at Barcelona and Bayern.
Matthew Howarth, Man. City reporter
City deserve enormous credit for a truly magnificent second-half showing at the Parc des Princes. Guardiola's team dug deep when required during the opening period and, despite an element of good fortune with the equaliser, Paris can have no complaints about the result. The tie is far from over, of course, but City head into next week's second leg firmly in the driving seat.
Kevin De Bruyne, Man. City midfielder: "In the first half we were too rushed. That's not the way we're set up as a team. In the second half we tried to find space more patiently. The progression we made as a team was good. We knew there were going to be moments where we were going to suffer. We knew we'd have to run hard but had the quality. That'll be the case in the second game too."
Josep Guardiola, Man. City manager: "Sometimes you need to be more relaxed. We changed a little bit the way we pressed [in the second half]. It's not easy against Neymar, Mbappé and Di María. I'm so satisfied with the performance. This club doesn't have much experience at this stage of the competition. All I want is for us to be ourselves in the second leg. We are good playing a certain way – we cannot do it differently."
Mauricio Pochettino, Paris coach: "We're very disappointed with the two goals. It's difficult to accept that this happened in the semi-finals – it's really painful. In the second half they were more consistent. It was difficult for us to cope. Physically they were a little bit more aggressive. It was difficult for us to recover the ball."
• Paris had won all eight previous UEFA Champions League matches in which Marquinhos had scored before tonight.
• Marquinhos is only the third player in UEFA Champions League history to score in the quarter-finals and semi-finals in consecutive seasons, after Cristiano Ronaldo and Antoine Griezmann.
• A Brazilian player has scored in the semi-finals in each of the past five seasons – Marquinhos has found the net in the last two editions.
• Manchester City remain the only unbeaten side in the UEFA Champions League this season and have won their last 18 away games in all competitions.
• Seven of De Bruyne's ten UEFA Champions League goals have come in the knockout stages.
• Mahrez is now the joint highest scoring Algerian player in UEFA Champions League history alongside Yacine Brahimi with eight goals.
Paris: Navas; Florenzi, Marquinhos, Kimpembe, Bakker; Gueye, Paredes (Herrera 83); Di María (Danilo 80), Verratti, Neymar; Mbappé
Man. City: Ederson; Walker, Stones, Rúben Dias, João Cancelo (Zinchenko 61); Rodri, Gündoğan; Mahrez, De Bruyne, Foden; Bernardo Silva
Paris are at home against Lens in Ligue 1 at the weekend while City visit Crystal Palace. This tie concludes in Manchester on Tuesday 4 May, with the winners taking on Chelsea or Real Madrid in the final in Istanbul on 29 May.