The PSG player was not marked, a free shot on target. However, I feel that maybe David can practise a bit more often on coming off his line more often.
I noticed PSG's tactic that most of their corners were quite deep in De Gea's goal, knowing that he won't come off his line, bringing his defenders in front of him under pressure.
After the first goal, it was quite comical to see that De Gea came of his line and tried for a punch clearance, hopelessly missing the ball and PSG almost scored with a deflection. Like he wanted to make amends for what happened earlier.