An embarrassing defensive howler saw Paris Saint Germain collapse to defeat against Manchester City in a breathless Champions League semifinal

• PSG collapsed to defeat against Manchester City in the Champions League semifinal.
• Two defensive errors and a red card saw the Ligue 1 side forfeit its early lead to lose 2-1.
• One of Manchester's goals was scored through a defensive wall from a free kick.

An embarrassing defensive mistake and a red card saw Paris Saint Germain collapse to a 2-1 defeat against Manchester City in the first leg of its Champions League semifinal tie on Wednesday.

PSG dominated the early proceedings at the Parc des Princes and was rewarded in the 15th minute when captain Marquinhos headed home from a corner.

City, much improved in the second half, then levelled in the 64th minute when Kevin De Bruyne's teasing cross nestled in the far corner of PSG's net past Keylor Navas, who failed to react quickly enough to keep it out.

Six minutes later, PSG made a huge blunder as Riyad Mahrez netted a free-kick from outside the box to give Pep Guardiola's side the lead.

He was aided by the fact that PSG's four-man wall had unforgivably split as the Algerian took his shot.

As the ball was struck, PSG central defender Presnel Kimpembe appeared to pull away from the ball, allowing it to go straight through a gap between him and teammate Leandro Paredes, and past a stranded Navas in PSG's goal.

Navas was visibly, and understandably, furious at his teammates, throwing the ball back towards the wall.

You can see footage of the goal below:

As City searched for what would have been a killer third goal, PSG's Idrissa Gueye was shown a straight red card for an awful challenge on Ilkay Gundogan, adding salt to the wounds of a night to forget for Mauricio Pochettino's team.

"There were two different halves - we did well in the first half but it is difficult to eliminate a team like City," said Pochettino after the match.

"We deserved to be ahead but they were better than us and dominated the second half. The two goals were accidents, but they created more than us. It was one half for each team.

"The two goals are very disappointing. It is difficult to accept but that can happen, and it has happened in a semi-final. It is very painful."

Guardiola said: "The first half is normal - you don't want to lose the ball [so] you don't play free. We changed a little in the way we press. We were passive, then we were more aggressive. It's not easy against Mbappe, Neymar, Di Maria.

"Afterwards we found goals and could have scored another. I'm so satisfied with the performance but we're only halfway. There are 90 more minutes. Anything can happen."

The two sides meet in the second leg at the Etihad Stadium on Tuesday May 4.