
Masking inadequacies? —
Bayern Munich faces a near impossible task of overturning a 3-0 deficit in the second leg of its Champions League semifinal tie against Barcelona. But while Barca will be favorite to progress, history suggests the tie is not quite over just yet...

They've done it before... —
Bayern has form when it comes to comebacks and its quarterfinal victory over Porto was just one example. The German side lost 3-1 in Portugal but turned it around at the Allianz Arena, scoring five goals in the first 40 minutes before easing to a 6-1 win.

Milan meltdown —
AC Milan looked destined to qualify for the last four of the 2004 Champions League after winning the first leg of its quarterfinal tie against Deportivo La Coruna 4-1. Having gone behind, the Italian side scored four goals in eight minutes, two of them to Brazil star Kaka, to seemingly seal a semifinal place.

Surely not? —
Deportivo required a 3-0 victory to progress on away goals but few expected the Spanish club to seriously threaten, even after Walter Pandiani's goal on five minutes.

Can you be serious? —
Deportivo sensed an opportunity and Juan Carlos Valeron added a second with a header before Albert Luque made it 3-0 just before halftime. Milan was in disarray at the interval and heading out of the competition.

Disbelief —
Deportivo fans could scarcely believe what they were watching as the might of Milan was torn apart. With just 15 minutes remaining, Fran netted his side's fourth of the night to give Deportivo a 5-4 victory. The result sent shockwaves through European football.

Facing embarrassment —
Liverpool reached the 2005 Champions League final dreaming of a fifth victory in the competition -- but by halftime the English team trailed 3-0 to Milan in Istanbul. Milan scored in the very first minute of the tie through Paolo Maldini before striker Hernan Crespo added two more before the interval. Liverpool's hopes appeared to be in ruins.

Can't happen, can it? —
When Liverpool needed him most, the captain responded. Steven Gerrard headed his side back into the game on 54 minutes to give fans the faintest glimmer of hope. What happened next was one of the most astonishing five minutes of European club football. First, substitute Vladimir Smicer rifled home from long range. Three minutes later, Xabi Alonso smashed home an equalizer after his penalty had been partially saved.

Nerves of steel —
Having somehow taken the game into extra-time, Liverpool survived the extra 30 minutes thanks to goalkeeper Jerzy Dudek. With no further goals, it was left to the lottery of penalty kicks to decide the contest. Milan striker Andrei Shevchenko needed to score to stave off one of the most famous defeats in European football -- but when his penalty was saved those in red danced their way through the night in utter disbelief.

Sealed with a kiss —
Gerrard lifted the cup and even took it to bed with him after the game following the dramatic victory. As for Milan, midfielder Andrea Pirlo summed it up best in his autobiography. "There are always lessons to be found in the darkest moments," he wrote. "It's a moral obligation to dig deep and find that little glimmer of hope or pearl of wisdom. You might hit upon an elegant phrase that stays with you and makes the journey that little bit less bitter. I've tried with Istanbul and haven't managed to get beyond these words: For f**** sake."

United blown away —
After a 1-1 draw in the first leg of its 1999 Champions League semifinal against Manchester United, Juventus looked certain to book a place in the final after a rapid start in the return match. The Italian side flew into a two-goal lead in the opening 11 minutes to move ahead 3-1 on aggregate.

The fightback —
Roy Keane, United's midfield enforcer, picked up a booking which would rule him out of the final if United somehow managed to produce a famous victory. That disappointment didn't appear to affect the captain though and he headed his side back into the tie with 24 minutes played.

King Cole —
United, trailing 2-1, hit back to level before the break through Dwight Yorke to ensure it led on the away goals rule. And with just seven minutes remaining, Andy Cole pounced to fire United into its first final in 31 years, where the English club defeated Bayern Munich 2-1 deep into added time.

Singing the blues —
In 2012, Chelsea needed to overturn a 3-1 first-leg deficit from its last-16 tie with Napoli. The Blues were in crisis, with head coach Andre Villas-Boas having been sacked and caretaker boss Roberto Di Matteo put in charge of first-team affairs. Whatever its problems, Chelsea made light work of its task at Stamford Bridge, moving into a two-goal lead before Napoli pulled one back. Frank Lampard's penalty took the game to extra-time before Branislav Ivanovic rifled home a dramatic winner. Chelsea went on to defeat Bayern Munich on penalties in the final.