Published: 2020-12-03 17:19:26 BdST
United, PSG and RB Leipzig all on nine points heading into next week's final round of games in which the English side go to the German club and the French champions host Istanbul Basaksehir.
It was surprising Fred was still on the field by that stage having received only a yellow card following a VAR review of an off-the-ball head-to-head clash with Argentine Leandro Paredes.
The pair were involved in a strong challenge later in the first half for which the Argentine was booked but despite having plenty of options on the bench, United manager Ole Gunnar Solskjaer decided against substituting Fred, a costly mistake.
Neymar fired PSG into a sixth-minute lead after a Kylian Mbappe shot was deflected and fell kindly to the former Barcelona forward who drilled the ball into the bottom corner.
United created several good chances after the break but failed to go ahead.
After good work from Edinson Cavani and Rashford down the right, Anthony Martial fired over the bar from a promising position.
Cavani was sent through and launched an audacious chip over the advancing Navas but the ball struck the crossbar -- Martial's follow up shot was brilliantly blocked by Marquinhos.
The Brazilian defender struck the bar himself with a looping header over David De Gea and the Spanish keeper pulled off a great save to keep out a low shot from substitute Mitchel Bakker.
Fred was dismissed after a foul on ex-United midfielder Ander Herrera as things fell to pieces for the home side.
Paul Pogba was thrown on and went close with a superb volley from outside the area but as United threw men forward they left holes at the back.
Mbappe powered through with a speedy run from deep but side-footed wide before the outcome was settled when Rafinha set-up Neymar for a simple tap-in.
PSG now have the head-to-head advantage over United and the easier task on paper next week while Solskjaer's men have plenty to do in Leipzig.