There was a time when this would have been a Fifty Shades Of Grey fixture.

Barça v Atlético, home or away, began to get a bit sado-masochistic.

The Catalans, generally, imposing the pain, the Madrileños accepting the humilation. Both kept turning up for more.

While Barça didn’t ALWAYS win, Atlético’s ten matches with the Blaugrana prior to Diego Simeone taking over saw them concede 36 times.

An appalling figure, more pertinent to primary school football.

Then, get this, when the now guru-figure of Simeone did take over the first three results were all defeats and cost another eight goals.

Thirteen games, three wins, 44 conceded.

Since Barcelona last won this fixture there have been five meetings between the sides and Los Colchoneros have conceded just twice in that time.

From allowing nearly 3.4 goals per game to 0.4 a match. That ain’t bad.

Filter out the games at the Calderón and it was much, much more embarrassing. Prior to this season, Atlético lost 26 goals in six visits to the Camp Nou, the very stadium in which the league leaders require either a draw or a win to give them their first Spanish championship for 18 years.

They were shipping in four a game. Crazy

The thing which helps establish beyond any doubt who is the most important man at Atletico, is the lineup from Los Colchoneros’ last defeat at the Camp Nou. In December 2012 Atleti took the lead against Barcelona. The XI which needed to defend that 0-1 lead for 59 minutes was: Courtois, Juanfran, Miranda, Godín, Filipe Lluis: Turan, Mario Súarez, Gabi, Koke: Falcao, Diego Costa.

It’s perfectly feasible that ten of those men take the pitch in Simeone’s starting XI on Saturday evening … and, dammit, you’d say that the presence of goal-matchine Falcao probably makes that a stronger side than the coach has at this disposal this weekend.

Fifty nine minutes later, however, they’d been trounced 4-1.

The previous Barça v Atleti result was 5-0. On that night the visitors fielded Courtois, Godín, Miranda, Mario Súarez, Tiago, Gabi and Diego – on the bench were Filipe Luis, Juanfran, Adrián and Arda.

Again, eleven players who might all be under the microscope as Spain’s Liga has it’s most high profile, most tense finale in history.

Simeone has taken all the same guys, added very little in terms of new talent, and completely transformed them from masochists to sadists.

Obviously, all this partly indicates how much Barcelona’s intensity, cutting edge, speed of play and individual brilliance has declined over the last ten months.

Leo Messi used to find scoring goals against Atlético, even when they had a knockout keeper like Courtois, easier than shooting goldfish in a barrel.

He’s now six meetings, and counting, without a goal or an assist against Los Rojiblancos.

• Will Messi bite back on Saturday? Find out his latest goalscorer odds here: Desktop | Mobile

Above all, those previous stats tell most about Simeone.

Yes, he’s working the team harder week in week out in training. Those who aren’t inspired by him are intimidated by him.

He demands that everyone train with at least as much, if not more, passion and appetite than they actually play with.

In that sense, if not in the philosophy of how games should be play, he’s Pep Guardiola’s brother from another mother.

But to take a group of men who were habitually used to being thrashed within an inch of their life (none of whom were ex public schoolboys) and to turn them into a stubborn, feisty, streetwise Dirty Dozen, as used to thwarting Barcelona as they were once beaten before the first whistle, is one hell of an achievement.

He’s succeeded in that most difficult of tasks – changing the psychology of an entire group. Unifying levels of hunger and confidence. Improving them

The ‘Cup Final’ mentality…

Twice in the last two seasons Simeone, evidently a terrific svengali figure for whom players will give ‘extra’ when they think they are empty and ready to punch the clock, has brought a winning ‘cup final’ end of term performance out of his troops.

Let’s call the Uefa Europa league final of 2012 and the Copa del Rey final of 2013 the direct equivalent of this ‘Cup Final’ which awaits Atleti on Saturday in Barcelona.

In 2012 Atleti weren’t quite supposed to be meat and drink for Athletic Club but the Basques’ performances that season, particularly in hammering Manchester United, indicated that they should have been properly threatening in the all-Spanish final.

Instead, Simeone’s Atleti were better from start to finish and in every possible department. They were fitter, they enjoyed the occasion more, they worked harder, they were cleverer and more effective – they completely bossed it.

A year later, again in a last-game-of-the-season-showdown, Atleti showed an utterly different characteristic. They fought and clawed to stay level with Real Madrid in the Copa Final and were grateful to Courtois for quite heroically keeping them in the contest.

They spent most of the night on the ropes but, via Miranda, they were still gutsy enough to produce the KO punch the instant that the opportunity presented itself.

• Can Diego Simeone mastermind another win for Atletico Madrid? Get the latest odds here: Desktop | Mobile

Simeone has taught them many things, he’s added some tactical finesse – but his greatest achievement has been psychological.

From a squad happy enough to coast along in third or fourth position and happy enough not to wave a guillotine blade at Spain’s ancien regime of Real Madrid and Barcelona, the Argentine has turned them into a bunch of bloodthirsty Robespierres.

Nerves at the finish line?

So, from my perspective, the big question to be asked before Saturday evening’s kick off is how much psychological damage has been done by Atleti losing five of the last six points at what should have been a ‘Vive La Revolution!’ moment of the season?

The loss at Levante was understandable enough. Having won at Chelsea and suffered the emotional tsunami of that experience the City of Valencia stadium was a horrible place to have to go and carve out a result.

But there was a general expectation that the champions-elect would swamp Málaga and there was a backwash of disappointment and deflation to discover, post that 1-1 draw last weekend that a single goal would have won them the title given Barcelona’s stalemate at Elche.

I watched the sagging shoulders, the dull, ‘dammit!!’ faces, and the suddenly weary bodies at the end of that Málaga draw, players, Simeone, technical staff and fans – and I thought that there’d been a major over-reaction

For a club so in charge of its emotions and psychology all season I thought that there was a glimpse of self doubt and a lack of ‘know-now’ in terms of that last push to get over the line.

From a bunch of guys who reckoned that a) the title would be won before going to the Camp Nou or b) that if they had to go and win they would and could, it felt as if Atleti had allowed self-doubt to corrode their previously robust confidence.

This should be treatable. A good, thorough working week on the Majadahonda training ground, individual tuition, perhaps a wee night out – there has been sufficient time since the Málaga draw to iron out and psychological kinks. You’d think, at least.

A further question is whether, improbable though it seems, Simeone has having a few flutters. Warrior, yes. Successful, yes. Invincible – no.

It’s vital that, should Atleti go one nil down (Barcelona haven’t taken the lead against these rivals for seven matches, since February 2012) they don’t suddenly get those ‘novice’ nerves which so often prevent ‘underdogs’ from fulfilling their vaunted potential.

Advantage Atletico?

Other than the body language last week, the omens are red and white. Not only do two of the three possible results win Atleti the title they’ve had significantly the better of things this season.

Atleti have the only win of the five games between the sides this term, Atleti have produced three different scorers and two different assist-givers against Barcelona since August.

Barcelona’s only scorer v Simeone’s mob this season, Neymar, won’t start and, realistically, shouldn’t even play at this stage of his injury rehab.

Atleti, at a time when Barcelona continue to look awfully ragged at the back without Piqué, Puyol or Valdés, keep on producing some lovely set plays – and scoring from them. Simeone’s guys at the masters of transferring hard work and planning from the training ground to the battlefield.

Then there’s the final point in terms of psychology. You’d have to forgive the boys in red and white IF they, consciously or otherwise, felt that their final against Real Madrid a week on Saturday is more important.

You’d forgive them if they decided to play speculatively (for a draw) at the Camp Nou and then, having reserved something, go ‘all-out’ in Lisbon against Real Madrid.

You wold forgive them, but would Barça? Tata Martino’s side has been patchy and unreliable due to oscillating form this season – but they’ve shown, to the cost of Madrid, Man City, Ajax, Milan and Villarreal, that when they really want to .. they can.

Mateu Lahoz, easily Spain’s best and most diligent ref, will be in charge. He MAY have a style which allows a Simeone-esque side more liberty with physical play but that’s because he likes the game to flow, not because he promotes brutality.

Barcelona used to be the perfect side to profit from Lahoz – quicker and brighter in how they reacted when an incident looked like a foul but the ref waved play-on.

He gives a premium to those who are quick, talented, who concentrate and love the ‘advantage’ rule.

Even though they’ve been too sluggish in every respect, recently, to draw benefit from his style, Barcelona have nonetheless never lost with Lahoz in charge

One more thought about Barça. They have the psychological impact of all these ‘farewells’ at the Camp Nou. From Tito’s unfair, untimely death through to Victor Valdés slinking away after a private goodbye to this team mates and Carles Puyol retreating with all guns blazing.

Full military honours there.

Do intangibles exist? Can Barcelona, slightly patched together where players’ form, fitness and energy levels are concerned, draw some sort of invincible emotional energy from the facts that Puyol and Valdés are going and Tito has gone forever?

More questions than answers. But a clear cut promise. IF Simeone has done his restorative psychology well, (as well as he’s managed with his squad all season) then Atleti will get their draw and their title.

If he hasn’t, then I suspect that this might prove to be a more vulnerable Atlético than Barcelona have faced in the previous handful of matches this season.

Game on.

• Get stuck in to the La Liga showdown with all the latest odds at PaddyPower.com: Desktop | Mobile

Want £200 Free? Click here to visit Bet365 and claim your free money.