Milan were torn apart on the night in 2004
This evening Arsenal host German giants Bayern Munich in the second leg of their last 16 encounter.
Arsene Wenger's team suffered a brutal 5-1 defeat in the first leg and they will need something close to a miracle if they are to progress to the quarterfinals. Arsenal would also be looking to write their names in the history books, as no team has ever come back from a four goal deficit in the Champions League knockout stages - a challenge Barcelona must also confront against Paris Saint-Germain.
The biggest comeback over two legs happened in 2004 when Deportivo La Coruna beat AC Milan 4-0, in their second leg match. Milan had been comfortable victors in the first game winning it 4-1. Hardly anyone gave the Spanish side a chance but against all odds they proved everybody wrong.
Ahead of the return fixture at the Riazor, Depor coach Javier Irureta was hanging onto little more than a dream.
"This is of course a very complex, difficult and challenging task," he said. "But in football, miracles often happen, things you might not rationally expect."
La Coruna didn’t waste time and were three goals to the good before the interval as Walter Pandiani, Juan Carlos Valeron and former Newcastle flop Albert Luque found the net. The away goal they scored in Milan meant that although it was four goals a piece on aggregate, the Spanish side were ultimately ahead in the tie at that point.
Importantly, the very first goal came after just five minutes of play against an off the pace Milan and an error from goalkeeper Dida for the second goal meant that Deportivo had quickly put themselves within a goal of progression.
And then 14 minutes from time they scored a fourth goal through club legend Fran to seal the victory and ensure their progression to the semi final.
Prior to the game, Irureta had said that if his side were to overturn the result from the first leg he would take the pilgrim trail to Santiago de Compostela, having prayed for success. “It is worth going to Santiago after this victory," he said. "I will do the walk to Santiago because a promise is a promise."