Paris Saint-Germain have been made to pay for two huge blunders in their Champions League semi-final first leg defeat at home to Manchester City.
The English side fought back from a goal down to score a 2-1 win at the Parc des Princes and take a crucial advantage into next week's decisive tie in Manchester.
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City reached the last four for the first time in five years under manager Pep Guardiola by also bouncing back from conceding an early goal in their quarter-final, second leg against Borussia Dortmund to win 2-1 in Germany.
The Premier League champions-elect needed a similar response after Marquinhos's early header gave PSG a half-time lead.
City were much improved after half-time, but had luck on their side to level when Kevin De Bruyne's cross found the bottom corner before Riyad Mahrez's free-kick completed the comeback.
PSG coach Mauricio Pochettino will be filthy with the way his side handed the advantage to City, with both goals coming via poor decision-making and execution from his players.
Goalkeeper Keylor Navas was grossly at fault for De Bruyne's 64th minute equaliser for City, after failing to get anything on the Belgian's teasing cross that ended up drifting into the far corner of the PSG goal.
Navas was then badly let down by his defensive wall less than ten minutes later when City were awarded a free kick outside the box.
All eyes were on De Bruyne as the City midfielder lined up to take the set piece, but his decision to leave it to the left-footed Mahrez proved a masterstroke.
The Algerian's effort wasn't high enough to clear the wall but a number of PSG players inexplicably turned their bodies as Mahrez kicked it, allowing the ball to sneak through a gap and into the back of the goal.
The shocking mistake was pounced on by viewers on social media as PSG's players care under fire from fans.
PSG's misery was completed late on when Idrissa Gueye received a straight red card in the 77th minute for a reckless challenge on Ilkay Gundogan.
City's dominance of possession after half-time and a fine defensive performance from Ruben Dias and John Stones managed to keep PSG's star duo of Neymar and Kylian Mbappe quiet.
But De Bruyne warned the job is only half done.
"We know there are going to be moments in the game where we suffer," added the City captain.
"The quality in this stage (of the competition), we know how good they are so you have to set your mind on that. Run hard, work hard for the team and we know we also have quality to play against them."
PSG will need to show the same away form that enabled them to beat Barcelona at the Camp Nou and Bayern Munich at the Allianz Arena in previous rounds if they are to progress.
"At halftime, I told the players we needed to be ourselves. We needed to be more aggressive and we didn't let them breathe after the break," City manager Pep Guardiola said.
"But it is halfway, so we still have many more minutes to beat them and PSG is a team where everything can happen."
City defenders keep PSG stars quiet
Chelsea drew 1-1 at Real Madrid in the other semi-final first leg on Tuesday.
Marquinhos, returning to the team from an injury suffered in the quarter-final first leg against Bayern, put PSG in front on Wednesday when he headed home Angel Di Maria's whipped corner in the 15th minute.
Guardiola's side lacked their usual composure in the first half, with Joao Cancelo picking up a yellow card for a woeful challenge on Kylian Mbappe.
City's first real chance came in the 42nd minute when Phil Foden tested PSG goalkeeper Keylor Navas.
The visitors were more attack-minded in the second half and they equalised on 64 minutes when De Bruyne, from a corner by substitute Oleksandr Zinchenko, sent in a cross and Navas failed to react as it curled into the far corner of the net.
Navas was beaten again seven minutes later when Mahrez's free kick deceived the PSG wall.
Pochettino vowed to go for broke when the teams meet again at the Etihad Stadium.
"In football, you need to believe and go there in six days and try to approach the game like today, try to win, to score goals," he said.
"Of course, the advantage is a little bit with Manchester City, but in football always you need to try."
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