It is quite magical how the intensity of the UEFA Champions League almost doubles whenever the European football competition leaves its group phase to enter the knockout stages.

The easy predictions and clear favourites go out of the window with almost every season seeing some major upset. With the 2020-21 UEFA Champions League round of 16 approaching its closure, we try to look back at three such ties that will be etched in memories forever.

AS Monaco vs Manchester City (2016/17)

The Ligue 1 2016-17 season was the historic campaign when AS Monaco had won the French championship buoyed by the emergence of a host of superstars. From Kylian Mbappe and Bernardo Silva to Fabinho and Benjamin Mendy, world football has seen an influx of some magical talents in one single season.

However, Monaco’s lack of experience was a worry for Leonardo Jardim against Pep Guardiola’s oil-funded star-studded side, which had Sergio Aguero, Raheem Sterling, Kevin De Bruyne, David Silva, Leroy Sane and more. The Cityzens were the overwhelming favourites and they rightly won the first leg 5-3 with Aguero’s brace leading the charge at the Etihad Stadium.

Having scored three goals away from home was all the encouragement that Monaco could muster, and they used it to their advantage well. Hosting City in the second leg, goals from Mbappe, Fabinho and Tiemoue Bakayoko saw Manchester City lose the match 3-1 and the tie 6-6, courtesy of away goals.

Barcelona vs Paris Saint-Germain (2016/17)

The 2016-17 UEFA Champions League season can rightly be labelled as the season of comebacks, given the grit and mettle showed by both underdogs and UCL giants in the round of 16 stages. Interestingly, going into this week’s UCL round of 16 second leg in Paris, Barcelona will look back at this fixture to garner all the optimism they need.

Pitted against a star-studded Paris Saint-Germain side in the round of 16, a high-flying Barcelona side were given a harsh reality-check at the Parc des Princes, where Angel Di Maria's heroic display saw PSG win the first leg 4-0.

The tie was realistically over with Barcelona having to overcome a mighty lead, but football is the stuff of dreams and the Blaugrana trident’s of Luis Suarez, Neymar and Lionel Messi managed the unthinkable.

Hosting PSG in the return leg, the forward trio scored four goals for Barca, apart from a Laywin Kurzawa own goal, before Sergi Roberto came off the bench to score a 95th winner as Barcelona won the match 6-1 and the tie 6-5.

Juventus vs Real Madrid (2004/05)

Things don't get any bigger than Real Madrid vs Juventus in the UEFA Champions League. And the line-up both the teams boasted of in the 2004-05 campaign could make any opponent shiver.

While Real Madrid's Galactico had the likes of Ronaldo, Raul, David Beckham, Zidane, Roberto Carlos, Figo and more, Juventus comprised the talented bunch of a prime Zlatan Ibrahimovic, Pavel Nedved, Fabio Cannavaro, Alessandro Del Piero, Lilian Thuram, Gianluigi Buffon and more.

The match-up was expected to be epic and so it did. Travelling to Santiago Bernabeu in the first leg, Juventus' sturdy defence held off Real Madrid quite effectively with an unlikely goal from Ivan Helguera being the only difference.

The star-studded Real Madrid side had almost pulled off a win in the second leg in Turin before David Trezeguet scored a 75th-minute goal to force extra time. The then Juventus coach Fabio Capello had engineered a different formation for the second leg, which unlocked winger Marcelo Zalayeta to bang home the winner in the 115th minute as Juventus won the close tie 2-1.

Feature Image Courtesy: AFP/ Pay Barrena