Diego Simeone's gang of gritty gladiators reached the quarter-finals of the UEFA Champions League by riding their luck to eliminate the holders with a magnificent rearguard defiance Helenio Herrera's 'Nerazzurri' would have been proud of 55 years ago.
The Spaniards fully deserved their overall 4-2 triumph, make no mistake, and Simeone would be entitled to be grateful to his men who scored a rare feat of beating Liverpool in their own backyard.
A shock it might have been but a fluke it certainly was not.
Yet some pertinent questions need to be asked.
Is Atleti's negative style an anachronism in an age when attacking football is a proven way to go?
Will Atleti ever win anything with a mentality designed to avoid defeat rather than seek victory in away matches?
Does it really matter 'how' a team wins if its club can lay its hands on the obscene riches available to modern winners?
Supporters of the 'other' team in Madrid would rightfully claim they could not care any less about the method of their victories.
But it remains to be seen if their reluctance to attack until they are forced to do so after falling behind - as was the case at Anfield - is good for the game at large.
All teams at any level play to their strengths and Atleti's big-match temperament and tactical discipline are certainly one of their plusses.
Liveroool boss Jurgen Klopp made a point afterwards that he could not understand why Atleti would play so defensively when they have so many fine players.
Simeone obviously believed that a more open approach would have been too risky and he unsurprisingly opted for extra caution and of course he had every right to do so, especially since this is not one of the finest teams he has handled since given the club reins in 2011.
As we all know, the game is about defending as well as attacking so to hell with entertainment: winning is everything, he would say.
Yet if the truth be told his tactics could so easily have backfired because Atleti looked a beaten side at two-nil down in extra time but they were given a reprieve by a howler from Liverpool's stand-in goalkeeper Adrian. That moment of madness changed the match.
Then at two-all the match as a contest was effectively all over before Alvaro Morata added insult to injury with a last-gasp winner.
Who knows? Had Liverpool scored their second goal five minutes earlier just before the final whistle Atleti would not have had any time to recover. Nobody would have complained about a 2-0 result.
Atleti will feel that the end justified the means and no doubt will continue to play this way in the latter stages of the competition (unless coronavirus dictates otherwise, that is) but they are unlikely to prevail at the business end.
Defensive football can win you some battles some of the time but it won't win you all the battles all the time.
Atleti will make a lot of money from this Euro campaign and they will invest it in better players so they can keep competing with the big guns every year.
However by persevering with such an antiquated style they will not win the one trophy that has eluded them for more than half a century.
