Last month, Manchester United, succumbed to a 2-0 defeat at home against Paris Saint-Germain, leaving them with all to do in the second leg at Parc des Princes.
It seemed like a mountain to climb for Ole Gunnar Solskjaer's Manchester United away from home, but they did their fans proud by hanging on and producing a comeback for the ages with their battling performance.
With Liverpool having sealed their place in their second consecutive Champions League final after a stirring comeback, we take a look at some inspiring comeback stories, and pick out the most memorable comebacks in the history of the Champions League.
7. Paris Saint-Germain vs Chelsea – 2013/14 Quarter-finals
Paris Saint-Germain flexed their muscles at home and picked up a comfortable 3-1 win over Premier League giants Chelsea. Eden Hazard's penalty kept the Blues barely alive in the tournament, but there wasn't much no hope for salvation.
In the return leg, the Blues came out all guns blazing at Stamford Bridge and cruised to a 2-0 win. Andre Schurrle and Demba Ba got on the scoresheet for the London club.
6. Real Madrid vs Monaco – 2003/04 quarter-finals
Real Madrid famed Galacticos cruised to a comfortable win 4-2 win against Monaco at the Santiago Bernabeu in the first leg of their quarter-finals. Sebastien Squillaci and Fernando Morientes scored two invaluable away goals for Monaco, which ultimately decided the tie.
In the second leg, Monaco registered a 3-1 win, with a Ludovic Giuly brace and Morientes' strike knocking Madrid out of the competition.
5. AC Milan vs Deportivo La Coruna – 2003/04 Quarter-finals
Serie A giants AC Milan had hoped for a straightforward quarter-final contest against the unpredictable La Liga side. Things went according to script in the first leg, as Milan picked up a 4-1 win at home.
In the return leg, Deportivo proved their mettle by pulling off something really spectacular. Walter Pandiani, Juan Carlos Valeron and Alberto Luque put Deportivo 3-0 at half-time before Fran Gonzalez scored to top off a historic night for the club.
4. Manchester United vs Paris Saint-Germain - 2018/19 Round of 16
Manchester United were down in the dumps after a 2-0 loss in the first leg of their Champions League round of 16 encounter against Paris Saint-Germain. Goals from Presnel Kimpembe and Kylian Mbappe had put the French giants in the driving seat ahead of the second leg.
Despite losing key midfielders like Ander Herrera and Nemanja Matic to injuries and Paul Pogba to a suspension, United pressed on from the start in the second leg, pouncing on errors from their opponents to take a 2-1 lead at half-time, with Romelu Lukaku scoring twice and Juan Bernat netting for Les Parisiens.
The Red Devils were awarded a late penalty after Kimpembe was adjudged to have handled the ball. Marcus Rashford stepped up and stroked it home calmly to give the Old Trafford outfit another famous night out in Europe as they moved to the quarter-finals.
3. Barcelona vs Roma – 2017/18 Quarter-finals
"This was not meant to happen, this could not happen, this is happening!" – Peter Drury's impeccable commentary perfectly captured the iconic night in Rome. Roma, after being thrashed 4-1 in the first-leg, somehow found it in themselves to mount a comeback in the return leg.
Edin Dzeko's goal and a Daniele De Rossi penalty put the pressure on Barcelona, before "Greek God" Kostas Manolas headed the winner in the 82nd-minute to hand Roma a 3-0 win.
2. Barcelona vs Paris Saint-Germain – 2016/17 Round of 16
FC Barcelona became the first team in history to overturn a four-goal deficit to win a Champions League tie.
The Blaugrana were hammered 4-0 in the first leg in Paris, virtually knocking them out of the tournament. Barcelona, however, made a historic statement in the second leg to etch their name in the history books.
A brace from Neymar, a Layvin Kurzawa own goal, and one goal each from Luis Suarez, Lionel Messi, and Sergi Roberto sealed a 6-1 win for the hosts.
1. Liverpool vs Barcelona - 2018/19 Semi-finals
Barcelona seemingly had the tie in the bag after securing a hard-fought 3-0 win in the first leg against Liverpool at the Camp Nou, thanks to a Lionel Messi double. The scoreline though, flattered the Spanish giants, as the Reds had failed to take their chances.
The second leg looked more like a formality as Jurgen Klopp was missing two of his trusted forwards in Mohamed Salah and Roberto Firmino. Despite their absence, the Merseyside outfit started the game with a bang, scoring through Divock Origi in the sixth minute.
Andy Robertson had to be substituted at half-time due to an injury and was replaced by Georginio Wijnaldum, who scored two goals to level the scores and give his team all the momentum going into the last 30 minutes of the match.
When Trent Alexander-Arnold made the clever decision to take a corner quickly after noting that the Blaugrana defence was not paying attention, Origi made no mistake and finished calmly to seal a 4-0 win and complete the comeback.
7 of the greatest comebacks in Champions League history