Chelsea must pull off one of the greatest second-leg comebacks if their Champions League hopes are not to be killed off by Bayern Munich on Saturday.
There has been a spate of stunning salvage jobs in recent seasons that may give hope to Frank Lampard's side, who trail 3-0 from the first leg in London.
Nevertheless, Bayern start as firm favourites to clinch a place in the quarter-finals heading into the clash at the Allianz Arena.
Here is a look at games that may give Blues fans some hope as their team head to Germany.
Bayern OR Chelsea?#UCL— UEFA Champions League (@ChampionsLeague) August 6, 2020
2019: Liverpool 4-0 Barcelona (4-3 on aggregate)
Jurgen Klopp's Liverpool had been well beaten at Camp Nou, with the 3-0 scoreline flattering Barcelona but making the Catalans clear favourites to complete their semi-final task at Anfield.
Liverpool were without injured forwards Mohamed Salah and Roberto Firmino for the second leg, yet two goals each from Divock Origi and Georginio Wijnaldum saw the hosts defy the odds in sensational style.
Origi had the final word thanks to Trent Alexander-Arnold's quick thinking from a 79th-minute corner.
It meant a Barcelona side boasting Lionel Messi and former Liverpool stars Philippe Coutinho and Luis Suarez were left devastated, while Klopp's men celebrated reaching the Madrid final.
Those full-time celebrations A year since THAT incredible night pic.twitter.com/H9SZIgTU2P— Liverpool FC (Premier League Champions ) (@LFC) May 7, 2020
2019: Real Madrid 1-4 Ajax (5-3 on aggregate)
Despite an impressive display in their 2-1 first-leg defeat, few thought Ajax could turn things around at the Santiago Bernabeu. Madrid's Sergio Ramos certainly did not - he earned a first-leg booking to avoid the risk of a quarter-final ban, earning an extra-game suspension from UEFA in the process.
In the absence of their captain, Madrid capitulated against a fearless and thrilling Ajax. Hakim Ziyech and David Neres put the visitors 2-0 up after only 18 minutes and it was 3-0 just after the hour mark thanks to the inspired Dusan Tadic.
Marco Asensio got a goal back, but Lasse Schone's free-kick beat Thibaut Courtois and sent Madrid crashing out. It was the first time Madrid had ever been knocked out after winning the first leg of a Champions League tie, while Ajax would themselves be stung by a comeback in the semi-finals.
2019: Ajax 2-3 Tottenham (3-3 agg)
Ajax looked certain finalists when they extended their 1-0 first-leg lead to 3-0 in Amsterdam with first-half goals from Matthijs de Ligt and Ziyech.
Mauricio Pochettino's Spurs took inspiration from Liverpool's stunning fightback against Barcelona 24 hours earlier, though, and Lucas Moura stepped up to emerge as their hero.
The Brazilian winger was thrust into a central attacking role and scored an improbable hat-trick in the second half, the vital third goal coming deep into stoppage time, as Spurs won on away goals.
2018: Roma 3-0 Barcelona (4-4 agg)
Barcelona were stunned in the Italian capital as Roma completed one of the most unlikely quarter-final turnarounds.
Eusebio Di Francesco's side came back from a 4-1 first-leg deficit to progress to the last four on away goals after a thrilling 3-0 win in front of their home fans.
Edin Dzeko, Daniele De Rossi and Kostas Manolas secured the 4-4 aggregate draw and sent the Stadio Olimpico into raptures, as Barca fell to pieces.
2017: Barcelona 6-1 Paris Saint-Germain (6-5 agg)
Before their humblings by Roma and Liverpool, Barcelona pulled off an astonishing Champions League comeback of their own, and the greatest so far in terms of the deficit overhauled.
Trailing 4-0 from the first leg of their last-16 tie with PSG, Suarez and Messi scored either side of a Layvin Kurzawa own goal, only for Edinson Cavani to grab what was expected to be the decisive away goal for the visitors.
However, two quickfire Neymar goals against his future club – the second a highly controversial penalty after an apparent Suarez dive – levelled the tie at 5-5.
Then, in the fifth minute of stoppage time, Sergi Roberto struck to create a slice of Champions League history – no side had ever turned around a four-goal first-leg deficit before.
Fim de jogo. FC Barcelona 6-1 PSG. Gols: Suárez, Kurzawa (contra), Messi, Neymar (2) e Sergi Roberto; Cavani. HISTÓRICO! pic.twitter.com/rUcRqrXNqm— FC Barcelona (@fcbarcelona_br) March 8, 2017
2004: Deportivo La Coruna 4-0 Milan (5-4 agg)
Deportivo were among Spain's major forces just after the turn of the century and one of their finest moments in Europe came in April 2004 when, despite being 4-1 down from the first leg of their Champions League quarter-final with Milan, they stunned the Rossoneri at the Riazor.
Walter Pandiani, Juan Carlos Valeron and Albert Luque had Depor ahead on away goals before half-time, with veteran Fran Gonzalez scoring the fourth to make sure of their passage.
Depor were eliminated by eventual winners Porto in the semi-finals, but this comeback stood as arguably the very best in Champions League history until Barca went one better.
2000: Barcelona 5-1 Chelsea (aet, 6-4 agg)
This is not one Chelsea will remember fondly.
A 3-1 first-leg loss at Stamford Bridge – having trailed 3-0 – had Barca in danger of being on the wrong end of a major Champions League upset prior to Chelsea's Roman Abramovich era, but in the return match the Catalan giants showed their true class.
Tore Andre Flo's 60th-minute goal was sending Chelsea through despite Rivaldo and Luis Figo scoring before the break, but Dani Garcia headed home seven minutes from the end of regulation to force extra time.
Rivaldo atoned for an earlier missed penalty by converting from the spot after Celestine Babayaro was sent off and Patrick Kluivert finished the game off, crushing Chelsea's dreams.