Manchester United suffered the heaviest home defeat in the club's European history in losing 2-0 at home to Paris Saint-Germain.
Second-half goals from Presnel Kimpembe and Kylian Mbappe earned PSG, without Neymar and Edinson Cavani due to injury, a comfortable win at Old Trafford on Tuesday.
To make matters worse for the Premier League side, both of PSG's goals were created by former United winger Angel Di Maria, who enjoyed a memorable return to the club.
Ole Gunnar Solskjaer's side had won 10 of his 11 previous games in charge across all competitions but injuries to Anthony Martial and Jesse Lingard proved damaging to their hopes of reaching the quarter-finals.
United will have it all to do in the second leg as none of the previous 34 teams to lose a home first leg of a Champions League tie by two or more goals have ever progressed.
And they will be without influential midfielder Paul Pogba in Paris on March 6 as the France international was dismissed in the closing stages, referee Daniele Orsato showing him a second yellow card after a foul on Dani Alves.