Overturning first-leg disadvantages is not a common occurrence and where the Red Devils are concerned, they have managed it five times in European competitions.
So, ahead of tonight's tie, Sports Mole reviews those quintet of encounters which have seen United prosper from a losing position.
1. Athletic Bilbao, 1957
On what was United's first venture into European football, they'd already seen off Anderlecht and Borussia Dortmund. Bilbao in the quarter-finals appeared to have been a step too far when they slumped to a 5-3 defeat in the San Mames, but during the second game at Maine Road, goals from Johnny Berry, Tommy Taylor and Dennis Viollet saw the English champions book their place in the semi-final.
2. Tottenham Hotspur, 1963
Dave Mackay was among the goals as Spurs recorded a comfortable 2-0 win at White Hart Lane, but he suffered a broken leg at Old Trafford, which hampered his team's chances of advancing because with no substitutes, the North Londoners had to continue with 10 men.
David Herd had already put United 1-0 up prior to Mackay's injury and the centre-forward added a second goal shortly after the restart. Despite their depleted numbers, Jimmy Greaves then put Spurs 3-2 up aggregate, but a late brace from Sir Bobby Charlton saw Sir Matt Busby's team win the Cup Winners' Cup tie 4-3 overall.
3. Ajax, 1976
A goal from Dutch international Ruud Krol during the first meeting in the Amsterdam ArenA gave Ajax a slender lead ahead of their trip to England. What's more, the visitors then spurned a handful of chances in the return match, while United goalkeeper Alex Stepney also made a host of saves.
United took full advantage, with Lou Macari scoring from close range after Gordon Hill's initial shot had been saved. Then, during the second half, Brian Greenhoff squared for Sammy McIlroy, who rolled in the winning goal to secure a place for Tommy Docherty's team in the second round of the UEFA Cup.
4. Barcelona, 1984
When United defender Graeme Hogg put through his own net inside the Camp Nou, it gave what many believed to be an unassailable 2-0 advantage to Barcelona from this quarter-final Cup Winners' Cup tie. Nobody told the Old Trafford crowd for the return leg, though. Speaking about the atmosphere that evening, then United manager Ron Atkinson told The Telegraph: "I've done big matches, I've managed in the Madrid derby, I've worked at World Cup finals, but I've never experienced an atmosphere like that, the noise was incredible. I heard stories that people like Peter Reid – who was not exactly a United supporter – were standing on their seats screaming."
On a night which marked Diego Maradona's first club outing in England, United responded to the support from their faithful, with captain Bryan Robson leading the way. He broke the deadlock by turning in a Ray Wilkins corner during the first half, then he pounced on a goalkeeping error to draw United level on aggregate.
© Getty Images
Then, before the crowd had been given a chance to regain their composure, Arthur Albiston's cross from the left was headed across the face of goal by Norman Whiteside for Frank Stapleton, who powered in from a tight angle to complete the comeback.
Reflecting on that night, Atkinson added: "The atmosphere played a massive part in our win. Even to this day, players who played and people in the stands - and Manchester United have had many great nights - would say, atmospherically, they have never known a night like that."
5. Roma, 2007
Paul Scholes saw red as United slipped to a 2-1 defeat during the opening match of their Champions League quarter-final in the Stadio Olimpico. With Italian clubs notoriously tight in defence, United's chances of reaching the last four appeared, on the surface at least, to be bleak. However, within the opening 44 minutes at Old Trafford, they had blown their visitors away.
Michael Carrick, Alan Smith, Wayne Rooney and Cristiano Ronaldo all found the back of the net before the break to put the home side in control. After the restart, Carrick and Ronaldo added further goals, while Patrice Evra rounded off the scoring nine minutes from time as United hit Roma, who scored a consolation through Daniele De Rossi, for seven.
"It was a fantastic performance by every one of our players. The speed of our play and our penetration was absolutely superb. That's absolutely the best night of European football we've had here," Sir Alex Ferguson said during his post-match interview.