Arsenal face mission impossible on Tuesday as they try to overturn a 5-1 deficit against Bayern, but they can maybe take some inspiration from these second-leg comebacks in the UCL?
Likewise, Barcelona will attempt to progress past PSG on Wednesday despite losing 4-0 away in the first-leg.
Neither has an easy task and both are unlikely to go through but there is hope.
As you can see in this list, the likes of Chelsea, Barcelona, Monaco and Deportivo have all completed remarkable turnarounds.
Do you think Arsenal can repeat any of these feats and advance past Bayern or is it all just a bit far-fetched?
Tells us and tag your friends in your predictions in either the comments below, using #360fans on Twitter or getting in touch via Facebook.
Barcelona v Milan, 2012/13 Round of 16
Barcelona had slumped to a shock 2-0 defeat in Milan, but two goals from Lionel Messi and strikes from David Villa and Jordi Alba meant Barcelona won 4-0 became the first team to overturn a two-goal deficit without the help of an away goal.
Chelsea v Napoli, 2011/12 Round of 16
The Blues’ 3-1 defeat in Naples had cost Andre Villas-Boas but back at Stamford Bridge, Didier Drogba, John Terry and Frank Lampard sent the game into extra-time – with Gokhan Inler making it 3-1 – before Branislav Ivanovic secured a 4-1 win.
Deportivo v Milan 2003/04 Quarter-finals
The most unlikely of turnarounds as Milan looked home and hosed with a 4-1 advantage from the San Siro. Yet, Depor advanced with a 4-0 hammering courtesy of goals from Walter Pandiani, Juan Carlos Valeron, Alberto Luque and Fran.
Monaco v Real Madrid, 2003/04 Quarter-finals
Monaco showed incredible resolve after losing 4-2 to the Galacticos in Madrid. At the Stade Louis II, Fernando Morientes – laughably on loan from Real – netted a brace and Ludovic Giuly scored for Monaco to win 3-1 and advance on away goals.
Barcelona v Chelsea, 1999/2000 Quarter-finals
After a first-leg 3-1 lead, Chelsea were just seven minutes from knocking Barca out at the Camp Nou after Tore Andre-Flo’s away goal. But Dani Garcia sent the match into extra-time before Patrick Kluivert and Rivaldo made it 5-1.