While Mauricio Pochettino's men beat Peter Bosz' Dortmund twice in last season's Champions League group stage.
"Teams that are struggling in their league have done very well in the Champions League".
Following the draw, Manchester City remain favourites for the competition according to the bookmakers, while Barca are considered second favourites.
FC Barcelona have been drawn against Olympique de Lyon in the Last 16 of the Champions League.
Champions league draw: Liverpool face Bayern Munich, Man Utd take on PSG
United, at a low ebb after Sunday's 3-1 defeat to Liverpool, meet PSG for the first time and a formidable task awaits against a side featuring Neymar and Kylian Mbappe - the world's two most expensive players.
Liverpool weren't much better, losing all three away games and this could come to trip them up in the knockout stages.
Well, we asked six of our writers to have their say.
Salihamidzic said, quoted by UEFA.com: "Liverpool are the hottest team right now and top of the Premier League table. Looking forward to it".
Ajax will play the first game at home on the 12, 13, 19 or 20th of February.
"Attractive football, a high tempo - they will be very hard to play against, especially with the second leg in Dortmund, with their fans and the yellow wall, the backing that the crowd gives them there".
Rep. Mark Meadows Under Consideration for Trump Chief of Staff
Trump is reportedly set to decide on a replacement by the end of the year, which corresponds to Kelly's scheduled departure. The official was not authorized to discuss the personnel issue by name and spoke on condition of anonymity.
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