Not so fast...

Don’t say you haven't been warned, PSG – you've been here before. Ole Gunnar Solskjaer is perky about Manchester United's chances of overturning a two-goal deficit at the Parc des Prices on Wednesday night, despite no team having ever done so following a 2-0 home defeat in the first leg.

History has also shown us that it’s never over until it’s over, though – as the following teams found out the hard way...

PSG vs Barcelona, 2016/17 (4-0, 1-6)

It was over. Nobody comes back from 4-0 down, even Barcelona. As for PSG, they were on the cusp of finally getting beyond the quarter-finals. They never made it.

No team had ever surrendered a four-goal advantage in the competition before, but Barça somehow managed to make history despite Edinson Cavani’s away goal making the task look almost impossible with less than half an hour to go and three more goals required.

It wasn’t just the feat, but the manner of it that was so memorable. In the 88th minute, Neymar scored a free-kick. In the 91st, he put away a penalty to take them to within one goal of a remarkable comeback. That goal, ridiculously, arrived in the 95th minute through Sergi Roberto. Utterly bonkers.

Deportivo vs Milan, 2003/04 (1-4, 4-0)

“For the first and only time in my life, I wondered if my opponents were on something,” Andrea Pirlo said after Milan exited the Champions League in stunning circumstances.

The Rossoneri seemed all-but through after a 4-1 first leg win at San Siro, but collapsed in Spain as Walter Pandiani, Juan Carlos Valeron, Albert Luque and Fran scored to send Depor into the next round.

Coach Javier Irureta stayed true to his word that he would make the 35-mile pilgrimage to Santiago de Compostela if his side managed to turn the tie around. He did, though, do it on his feet, not on his knees as he originally pledged. Lightweight.

Monaco vs Real Madrid, 2003/04 (2-4, 3-1)

When Real Madrid made the decision to send Fernando Morientes out on loan to Monaco, they expected it to give him some game time that could lead to a big-money departure the next summer.

What they didn’t expect was that it would be mean the end of their Champions League ambitions.

The striker scored a vital away goal during Monaco’s 4-2 defeat in the first leg at the Bernabeu, before heading home another in the second leg between two Ludovic Giuly strikes as the French side went through on away goals.

Bayer Uerdingen vs Dynamo Dresden, 1985/86 (0-2, 7-3)

The pressure was on Dresden to get a result against their West German rivals in this Cup Winners’ Cup quarter-final, after the Stasi insisted that they reached the last four.

They won the first leg 2-0 and looked set for comfortable progression when they held a 5-1 aggregate advantage by half-time.

However, it all unravelled when Uerdingen scored six goals in just half an hour to go through and enrage the East German overlords. Dresden striker Frank Lippman fled to GDR and never returned, while manager Klaus Sammer was sacked for shaming the nation. Uerdignen went out in the semis against Atletico Madrid.

Inter vs Bayern Munich, 2010/11 (0-1, 3-2)

Having beaten Bayern in the 2010 final, Inter were again their tormentors in becoming just the second team to overturn a first-leg home defeat in the Champions League era.

Mario Gomez’s stoppage-time winner had put the Bavarians in control three weeks earlier, but Samuel Eto’o, Wesley Sneijder and Goran Pandev responded to another goal from Gomez and one from Thomas Muller to send the Nerazzurri through on away goals.

However, the Italians then suffered a 7-3 aggregate thrashing at the hands of Schalke in the quarter-finals.

Metz vs Barcelona, 1984/85 (2-4, 4-1)

Barcelona’s Bernd Schuster kindly offered to “give the Metz players some ham to thank them for all the presents they’ve given us tonight” after the Catalans won their Cup Winners’ Cup first round first-leg tie in France.

French media didn’t even bother travelling to the Camp Nou for the second leg, which looked to be fair enough when Metz went 5-2 behind on aggregate.

However, the Ligue 1 side launched an extraordinary comeback, achieved thanks to a stunning Tony Kurbos hat-trick. Metz keeper Michel Ettorre was particularly chuffed, beaming: “At full-time I ran straight up to Schuster and bawled ‘Where’s your ham now?’”

Odense vs Real Madrid, 1994/95 (2-3, 2-0)

Until their humiliating capitulation against Ajax, Real Madrid had only ever lost a UEFA tie after winning the away leg first once – and that came against Odense.

Los Blancos triumphed 3-2 in Denmark thanks to a late winner from local hero Michael Laudrup, and the fans were so confident of a cakewalk back in Spain that only 30,000 of them turned up.

However, Odense got one on the board with a quarter of an hour remaining, and then Morten Bisgaard smashed a shot past Santiago Canizares to sensationally turn the tie on its head. The Danes were eventually eliminated in the quarter-finals by Parma.

Ajax vs Panathinaikos, 1995/96 (0-1, 3-0)

The Panathinaikos fans were ready for a party when Ajax visited in the second leg of their Champions League semi-final, having recorded a 1-0 win in Amsterdam.

77,000 supporters filled the Olympic Stadium in Athens, but they were left stunned when Louis van Gaal’s young team ran riot. Two goals from Jari Litmanen and one from Nordin Wooter meant they became the first team of the Champions League era to overturn a first-leg home defeat.

It wasn’t ultimately enough to push Ajax all the way, though, and they fell in the final to Juventus after a penalty shootout.

Real Madrid vs Derby, 1975/76 (1-4, 5-1)

Dave Mackay, Brian Clough’s greatest signing of his glorious period in charge of Derby, led the Rams into their second European Cup campaign and soon came up against the giants of Real Madrid in the second round.

Charlie George put three past the Spanish side in a superb 4-1 home win to set them up for a trip to Madrid.  “We arrived two days before the [return] game and had time to do some sightseeing – though nowadays there would be no walking around a city for hours,” Archie Gemmell recalled.

However, they didn't enjoy what was to come: Los Merengues smashed them 5-1 in front of 120,000 fans at the Bernabeu.

Bayer Leverkusen vs Espanyol, 1987/88 (0-3, 3-0, 3-2 pens)

Espanyol had one hand on the UEFA Cup after beating Bayer Leverkusen 3-0 in the first leg of the final.

But Leverkusen responded and won by the same margin on home turf, despite waiting until the 57th minute to take the lead before Falko Gotz and Cha Bum-kun added late goals.

And so the match went to penalties where, predictably, the Germans came out on top. The game became known as The Tomb of Leverkusen to Espanyol fans, while the Bundesliga side remain the only club from Germany to win a European competition but never their domestic league.

Partizan Belgrade vs QPR, 1984/85 (2-6, 4-0)

QPR were in prime position for UEFA Cup progression after smashing visiting Partizan 6-2 in their ‘home’ game at Highbury, where they played due to the plastic surface at Loftus Road.

However, Alan Mullery’s side were dismantled 4-0 in Yugoslavia and eliminated on away goals.

“Mullery chased us down the tunnel telling us to come back for extra-time,” said goalkeeper Peter Hucker. “He didn’t even know the rules.” Unsurprisingly, the boss was sacked weeks later.