Atalanta's players crumpled to the turf dejected, crestfallen and beaten.

Gian Piero Gasperini's side were a had been half a minute, plus stoppage time, away from a place in the Champions League semi-finals before late goals by Marquinhos and Eric Maxim Choupo-Moting saw Paris Saint-Germain break their hearts in Lisbon.

It concluded a season of unlikely triumph surrounded by crushing tragedy for the club and their city of Bergamo.

As they prepare to host Real Madrid on Wednesday, memories of their previous Champions League home game remain vivid, yet feel like they are from another time altogether.

'Game zero'

On February 19 last year, around 40,000 Atalanta fans – a shade under a third of Bergamo's population – packed themselves into coaches and train carriages and headed to Milan.

San Siro was hosting La Dea's European home games as the Gewis Stadium underwent renovation. Two-time finalists Valencia were opponents who soon discovered such pedigree counted for nothing.

Gasperini's men scythed through Los Che irresistibly, chalking up a riotous 4-1 win amid scenes of delirium in the stands.

On February 20, Bergamo's mayor Giorgio Gori learnt of the first reported case of COVID-19 in a nearby town. As the early weeks of the pandemic unfolded, his city was ravaged. By the beginning of April there had been 2,245 declared deaths, with local newspaper Eco di Bergamo estimating the figure to be closer to 4,500 over the course of March.

Other factors, such as an outbreak in a local hospital, played a part in Bergamo's devastating collective tale, but Atalanta's thrashing of Valencia being alternatively described as "game zero" and a "biological bomb" cast a shadow over one of the finest night's in the club's history.

Yet, when games returned in empty stadiums, Atalanta motored on with an outside bid for the Scudetto. They led twice against eventual champions Juventus before two Cristiano Ronaldo penalties pegged them back to a 2-2 draw.

From that point, they won only three of the final six games of a relentless Serie A schedule, with PSG then benefitting from being taken deep by a team running on empty.

The plan was to keep the side together and challenge again this time around – something that has been accomplished despite one notable exception.

No Papu, no party?

If one player embodied both the swashbuckling brilliance of Gasperini's Atalanta and the close bond between club and city that only became stronger during the pandemic, it was Papu Gomez.

Signed to a squad battling relegation in 2014, the Argentinian playmaker transformed the club in tandem with Gasperini as their captain and creative inspiration.

Last season, as they scaled new heights, he created an astonishing 120 chances across all competitions. Among players from Europe's top five leagues, that placed Gomez joint fifth and a place ahead of compatriot Lionel Messi (116).

In an interview with El Pais, the 33-year-old revealed an unusual secret to his craft. He takes his positional cue on the field from the referee because the official is always in space.

Such maverick, intuitive quirks made Gomez the often unplayable jewel at the centre of Gasperini's sparkling, shifting attack. Both men are heroes to the extent they have been granted the freedom of Bergamo.

Gomez was majestic in the 2-0 group-stage win at Liverpool but only played four more times for Atalanta as the love story came to an abrupt end.

During a 1-1 draw against Midtjylland – Atalanta enter the Madrid game still seeking a first Champions League win at their own ground – Gomez and Gasperini became engaged in a tactical dispute that resulted in the skipper being substituted at half-time.

From that point he was used only when absolutely necessary against the very best, completing 90 minutes as La Dea sealed qualification at Ajax's expense with a 1-0 win in Amsterdam, before coming off the bench to help claim a 1-1 draw at Juventus.

In the transfer window, he was sold to Sevilla. Champions League money and a windfall in the region of €85million from the sales of Dejan Kulusevski and Amad Diallo mean Atalanta do not have to seek buyers. Gomez and Gasperini's relationship was one simply deemed beyond salvaging.

If, at that moment, it felt fair to predict the end of the fairy story of a club punching hugely above its weight to gate crash Europe's elite, two prolific strikers had other ideas.

Colombian double shot

Following a senior international breakthrough with Italy this season, Matteo Pessina has generally taken Gomez's place in Gasperini's 3-4-1-2, although 24 chances created in as many appearances shows a significant shortfall on his former team-mate's astonishing numbers.

That is not to say Pessina, with his astutely timed runs to combined with the forwards, does not contribute strongly, but Atalanta have had to find other ways through.

In 16 games since Gomez last featured in the Juve draw, they have lost once, beating Roma 4-1, Sassuolo 5-1, Milan 3-0 and, last weekend, Napoli 4-2. They also saw off Gennaro Gattuso's side to reach the Coppa Italia final.

The common theme in those heavy wins was Colombia strikers Duvan Zapata and Luis Muriel getting on the scoresheet.

Despite starting just eight Serie A matches this season, Muriel has 14 top-flight goals. He is a super-sub beyond superlatives.

His minutes-per-goal ratio of 73.1 is the best for players in Europe's top leagues across all competitions. His 17th of the campaign against Napoli last time out meant he began this week ahead of Erling Haaland (78.9) and Robert Lewandowski (81.9).

Gasperini has started his strike duo together more frequently over recent weeks, perhaps anticipating more consistent returns than those promised by the exquisite but mercurial Josip Illicic, but their starter-substitute double act has often proved impossible for defences to combat.

Zapata is not enjoying his best season in front of goal. Like Lewandowski, he has missed 22 of what Opta terms "big chances" but has only netted on nine such occasions to the Poland superstar's 23.

Nevertheless, he has still weighed in with 13 goals overall and always serves the purpose of extending centre-backs to their physical and technical limits before a forebodingly fresh Muriel comes on to make hay.

His electrifying pace is a nightmare for tiring defences, as evidenced by seven goals from his own carries. Only Tottenham's Son Heung-min (nine) boasts more in the big five leagues, while Muriel has laid on three further goals in similar fashion.

Going to the dentist

Muriel and Zapata are simultaneously part of and beneficiaries of a tireless team effort that further explains Atalanta's success.

After his side's 1-1 draw at San Siro in last season's Champions League, Manchester City boss Pep Guardiola said playing Gasperini's team was "like going to the dentist".

It was a reference to the pressing game that can feel like an invasive root canal procedure for opponents.

In Europe's top five leagues, only Bayern Munich (278) had made more high turnovers than Atalanta's 259, with La Dea turning those into 39 shots and five goals (fourth and joint fifth best, respectively).

All teams have had to make some allowance for the fatigue of a compressed season and Atalanta's approach is not quite as ravenous as it was. They allow opponents an average of 10.3 passes per defensive action (PPDA), down from 9.3 last season – which was the best in Italy and third in Europe.

Even so, for high turnovers, high turnovers ending in shots and pressed sequences they lead the way in Serie A. There promises to be little respite for an injury-hit Madrid.

They also have the highest defensive line in Italy, with Opta data showing Atalanta's attacks start on average 45 metres from their own goal – a figure in line with Bayern, Liverpool and City.

This does mean a defence susceptible to collapse on occasions. This season's wins over Napoli and Liverpool avenged 4-1 and 5-0 losses, while a 3-3 draw from 3-0 up against Torino earlier this month put any lingering Scudetto hopes in perspective.

Still, the role of Atalanta's midfield driving force Remo Freuler should not be underestimated when it comes to filling in those shaky foundations.

The Switzerland international was absent for the Napoli and Torino setbacks. Indeed, Atalanta's record without Freuler on the field reads drawn two and lost two in 2020-21, set against a 62 per cent win rate when he features.

Freuler, Zapata and Muriel are all set to be key against Madrid, who are trying to avoid a third consecutive last-16 exit.

So, what are the chances of an upset?

"With all the respect in the world, Atalanta are a wonderful team playing very offensive football," former Madrid captain Fernando Hierro told AS.

"But in our time, the Italian clubs we met were of a different calibre. That's why Madrid must now have faith in their abilities because Atalanta are not a team to be intimidated by."

Perhaps not. But after weathering life at the epicentre of Europe's coronavirus crisis, brushing off the bitterest of Champions League defeats and marching on despite unexpectedly losing their best player, it feels fair to wonder why on earth Atalanta would be intimidated by Real Madrid.