Champions League quarterfinals: Underdogs eye upsets in one-off format as Bayern and Barcelona head four ties in four days (VIDEO)

Five of the eight European giants heading to the Champions League mini-tournament in Lisbon have never reached the final, while one of the two former winners will be knocked out on Friday. Here's a guide ahead of the one-off ties.

Atalanta vs Paris Saint-Germain (Wednesday)

The lowest-ranked team left in the competition by a considerable distance at 50th – next nearest quarter-finalists Leipzig are 18 places above them – Atalanta are the reliably exciting tournament underdogs and the only side making their Champions League debut this season.

Of the five players to have scored more than 10 goals for the Serie A swashbucklers during the current campaign, Duvan Zapata and Luis Muriel are each a goal behind the 20 scored by Josip Ilicic, the Slovenia striker responsible for all of their goals as they won 4-3 at Valencia in March, having beaten the Spaniards 4-1 in the round of 16 first leg the previous month.

Bankrolled by outrageous wealth and spearheaded by the world’s most expensive footballer in Neymar, PSG could never be accused of being overlooked but would be a new entity should they reach the semifinals, having not reached that stage since the European Cup of 1995.

With Lique 1 abandoned since they last played in the Champions League, the French champions’ lack of competitive action could be beneficial or a hindrance. That unknown aside, their 2-0 win to overturn a first-leg deficit against Dortmund in March was an impressive announcement of their genuine status as contenders this year.

They were left sweating on the fitness of star forward Kylian Mbappe after he limped out of the French Cup final against Saint-Etienne, but the World Cup winner has since returned to training and while he may not be risked for the Atalanta showdown, he will likely be ready should PSG progress beyond that. 

Leipzig vs Atletico Madrid (Thursday)

Julian Nagelsmann is the youngest coach to reach the Champions League quarterfinals, leading the club to this stage for the first time in their history with a consummate 4-0 aggregate win over last season’s finalists, Tottenham. That included a decisive penalty from 32-goal top scorer Timo Werner in the first leg in London, although the young star will be missing for the quarterfinals after making the move to Chelsea.  

Marcel Sabitzer has been Werner's equal in the tournament so far. Two of the Austria midfielder’s four goals in Europe came within the first 21 minutes at home to Spurs, although Atletico will hope their notoriously tough defense can avoid any repeat of that.

Jurgen Klopp railed at the approach that kept Liverpool out as Diego Simeone’s side won 1-0 in the first leg of the round of 16, only to look somewhat silly in the second leg, when the visitors scored three in the final 13 minutes of extra-time to seal a 4-2 aggregate win at Anfield.

Atletico have not always sparkled this season, losing twice in the group stages of the Champions League and narrowly avoiding fourth in La Liga, but there has been a sense of them delivering when they need to. That cunning could tell against inexperienced opponents.

Their preparations have, however, been disrupted by the news that two unnamed individuals within the camp – which reports in Spain claim are players – have tested positive for Covid-19, placing doubt over their travel and training plans.   

Barcelona vs Bayern (Friday)

There are mixed omens in arguably the clash of the quarter-finals. Barcelona beat Bayern 6-2 on aggregate in the 2015 semifinals in a tie that looked largely over after Barca had won 3-0 at home in the first leg, including two goals from Lionel Messi.

Bayern, however, will be looking to invoke the spirit of 2013, when they recorded a seismic 7-0 victory over Barca across two legs, going on to win the tournament, as their victims did following their revenge two years later.

Barca probably have more to fear here. Bayern and tournament top scorer Robert Lewandowski, who has found the net 13 times, have a flawless record this season, including six group stage wins and a 7-1 victory that made Chelsea look helpless in the round of 16.

A frequently troubled season is no reason to discount a side that contains Lionel Messi and Luis Suarez, easing past an admittedly off-color Napoli in cooler fashion than might have been expected on Saturday.

The pressure on Quique Setien to produce after a dismal end to the Liga could bring out the best in his maligned tactics and squad.

Manchester City vs Lyon (Saturday)

Pep Guardiola will go 10 years without winning the Champions League should Manchester City fail to win the tournament that they were at risk of receiving a future ban from.

His hatchet job on Real Madrid’s sleepy defending on Friday, though, showed that he has every chance of leading City to European honors in a season when they were comprehensively dethroned as Premier League champions.

Gabriel Jesus and Raheem Sterling have six goals each for their unbeaten side after the 4-2 win over the Liga champions, which is also how many dangerman Memphis Depay has for Lyon, including the early penalty that set them on their way to a surprisingly comfortable ousting of Juventus, if an away goals win can be described that way.

Young midfielder Houssem Aouar is a precocious creative force, and Lyon’s win at City last season is a reminder that the team who finished seventh in Lique 1 are a threat to Guardiola’s ambitions.