Paris Saint-Germain boss Mauricio Pochettino believes that Real Madrid's first goal on Wednesday night should not have stood.
Karim Benzema put pressure on Gianluigi Donnarumma as the Italian dallied on the ball in the box, ultimately leading to him losing possession and the Frenchman scoring.
"There's a feeling of a lot of injustice," Pochettino said after the game. "Because of the goal.
"It was a clear foul from Benzema on Donnarumma. The emotional state of the game changed and we were exposed. It was a big blow because we were the better team in the tie.
"We had the better of the 180 minutes, but Real Madrid had nothing to lose at 1-1 and threw everything at us."
Although Donnarumma came in for criticism, the Argentine coach defended his goalkeeper.
"It's not a mistake because it was a clear foul," Pochettino insisted. "I've seen it 30 or 40 times from every angle.
"It wasn't a mistake, it was a foul. Small details count and VAR hasn't seen a decisive foul.
"It was a determining factor that influenced the mood of the two teams and the stadium. We had been in control."