Mbappe stars as PSG hand Solskjaer's Man Utd a reality check

Kylian Mbappe celebrates scoring PSG's second goal at Old Trafford

But for the saves of David De Gea, United would have lost by a heavier margin, but this was still their heaviest European defeat at Old Trafford; prior to this, United had not been beaten by more than one goal at home in over 60 years.

What: Manchester United will host Paris Saint-Germain in the first leg of the Round of 16 in the UEFA Champions League.

But Solskjaer admitted that PSG were on "another level" but that he expects his players to respond positively and insisted it was "not impossible" to overturn a 2-0 deficit in the second leg in France on March 6, despite the "big blow" of Paul Pogba being suspended after his red card.

In the absence of Neymar and Edinson Cavani, much of the pre-match focus was on teenage sensation Mbappe, but it was the ex-Real Madrid man that will have caused Solskjaer the biggest headache ahead of the second leg.

The most notable thing to happen in the first act was Italian referee Daniele Orsato sparing Kimpembe a second yellow card within the first half hour and then declining to send Ashley Young off for shouldering Angel Di Maria into fencing surrounding the field, when he'd been cautioned already as well.

"It was a new system and we weren't really used to it", Mbappe said.

The second goal, on the hour, was the culmination of an electric counterattack.

"I can't do anything about Alexis Sanchez", said Solskjaer.

It was all a sharp contrast to when the last-16 draw was made and the cloud of Jose Mourinho's final days in charge loomed over a United side viewed as the plum Premier League pick for Europe's elite.

Paris Saint Germain's Presnel Kimpembe, right, celebrates after scoring the opening goal the game. "I just want to keep enjoying my football, being useful to the club and my team-mates, whether on the field or if needed off it". "When he plays, he needs to find himself because we know there's a quality player there".

Two goals from 19-year-old Nicolo Zaniolo earned AS Roma a 2-1 win against Porto in Wednesday's other match. Momentum can take a team only so far and Tuchel, the highly rated former Borussia Dortmund coach, showed the need to be tactically astute to win on a stage as unforgiving as the Champions League knockout rounds.

"It's not going to be a season defining one, it's one we have to learn from".