Such a devastating loss followed by a summer exodus of top players would normally be enough to derail the aspirations of any team, but not Atleti.
One of Spanish football’s stars of the future, Koke, ignored the overtures of Barcelona to continue his education under the manic but irrepressible Argentine.
Ditto Diego Godin, Miranda, Juanfran, Gabi and Arda Turan.
Add the exciting Antoine Griezmann and robust Mario Mandzukic to the mix and it’s easy to understand why many experts are tipping Atleti for success again this year.
In Simeone, the club have a manager who is the embodiment of what Atletico Madrid are all about. Hard-working, diligent and direct, Simeone demands as much of himself as he does his players.
Real Madrid, arguably many pundits tip for UCL glory again this season, have been dispatched in both the Spanish Supercup and La Liga by the craft and guile of Simeone’s charges.
A studious ethic continues to ensure that Madrid’s “other” team are well able to cope with the loss of their best exponents, and why there is an air of confidence around the Vicente Calderon that the team can go one better this season.
Group A sees Atleti paired with Italian giants Juventus, Sweden’s Malmo and the Greek champions.
Juve are the main obstacle to Atleti finishing as group winners but they could be hurt by the loss of manager Antonio Conte to the Italian national side.
The former Bianconeri midfielder ended each of his three seasons with the Scudetto, his first unbeaten and his last with a record 102 points.
His bond with players, staff and supporters alike draws obvious comparisons with Simeone but even without him, any team that can boast the likes of Andrea Pirlo, Arturo Vidal, Paul Pogba, and Carlos Tevez in their ranks must be taken seriously as challengers.
Outsiders Malmo have their work cut out. Only once before have they had experience of the group stages of European competition, drawing one and losing five as they finished bottom of their 2011/12 Europa League group.
Already well into their league season, the Himmelsblatt (Sky Blues) can take some heart from only having lost two games since the beginning of May this year.
If things were different, England manager Roy Hodgson could still be in charge at the Swedbank Stadion after being offered a lifetime contract because of his huge success there in the mid 1980’s.
Still popular in the region even now, ‘Royson’ is affectionately remembered and there is even an unofficial “Roy’s Corner” in one of the stands at the ground.
And so to Atleti’s first opponents Olympiacos.
Former Real Madrid and Spain midfielder Michel has a side that should certainly be afforded appropriate respect at the Karaiskakis Stadium.
It’s worth mentioning that recent opponents such as Manchester United, Arsenal, Borussia Dortmund and Benfica have been sent home from Greece with their tails between their legs.
Michel can call on quality all over the pitch and if Alejandro Dominguez is allowed time to scheme in the midfield – as he was against United – then the Spanish champions could well come unstuck.
Kostas Mitroglou too will be desperate to prove that his spectacular failure at Fulham was just a blip.
The teams have met once before in Europe. The 1992-93 UEFA Cup Winners Cup Quarter Final saw a 1-1 draw in Greece before a 3-1 Atleti triumph at the Vicente Calderon saw the Spaniards through.
It promises to be a lively start to another European campaign. Just the way Simeone likes it.
How will Atletico fare this season in the Champions League? Can they go one better than last year and win it?
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