It’s odd after the Catalan euphoria of a 0-2 win at the Etihad in the first leg that subsequent power-plays by the two Madrid clubs (Atletico 5-1 winners over Milan, Real Madrid 6-1 up on Schalke) that Barça somehow profile as the ‘weak’ man of the Spanish Champions League trio.

The aura which they re-established that night in Manchester, whispering reminiscences of better times gone by, has been dissipated by subsequent horror-shows in La Liga.

Add the fact that it’s now palpably clear that Mauricio Pellegrini should have dictated a faster-paced, high-pressure, high-up-the-pitch strategy in the first leg (patented in Barça defeats by Valladolid and Real Sociedad) and there’s the whiff of a shock drifting over the Camp Nou.

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Vincent Kompany, all seriousness and articulate football analysis in the press room of the Camp Nou on Tuesday, very evidently felt that football inherently provides great nights, great shocks like City will need but also warned that at the first sign of complacency from the visitors that Barcelona are easy meat and ‘the beast might awake’.

Those who favour City will talk about Barcelona’s defence. It’s not a false point but I think it also misses the key issue. It’s in midfield where Barcelona have begun to be over-run.

Attack is the best form of defence

When the Catalans were at their very best the defence began with the front three – perm from Pedro, Leo Messi, Samuel Etoo, Thierry Henry and David Villa.

For opposition defenders it was simply less hassle to get shot of the ball than put up with Blaugrana strikers, backed up by midfielders or wing backs, nipping and snarling around their heels.

By definition this meant that the midfield was almost always on the front foot.

Xavi, Iniesta, Busquets, Yaya Touré and Seydou Keita et al were constantly picking up the scraps of possession won by the front three relatively high up the pitch and immediately pressing the advantage the way that the forward line pressed the ball – with urgency and intelligence.

All of this meant that with predictable regularity the majority of the defending which Barcelona’s back line did was based on anticipating trouble coming, reading it, intercepting it and, more regularly than right now as teams score from set plays or shoot early, relying on Victor Valdes making one-on-one saves when the defensive line was penetrated.

Currently neither of the two lines in front of them are protecting the Barça defence the way they once did.

While I would argue that both Dani Alves and Javier Mascherano are making consistently flawed decisions on positioning and when/when not to  tackle, the impression that the roof is falling in on the Barcelona back four is exacerbated by: how much extra work they are having to cope with; what their role was originally constructed by Pep Guardiola to be (largely offensive) and how deep they feel obliged to play.

Which leads to the fundamental decision facing Tata Martino with regards to team selection, team formation and the philosophy of how to control this tie tonight.

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By his own admission after the first leg against City the cluster of matches (Sevilla, Rayo Vallecano, Real Sociedad and the match in Manchester) not only had the Spanish champions played well, controlled matches won with style or qualified for the Cup Final (against Real Sociedad), Barcelona had managed to concede very few chances on goal.

Part of his success was to tamper with the outright 4-3-3 formation, where the front three are all pure strikers, and to ensure that as often as possible Andres Iniesta, Xavi, Sergio Busquets and Cesc Fabregas are united in the same team.

More, when either Iniesta or Cesc is named in the front three but, effectively performs like an (attacking) midfielder Barcelona’s shape is 4-4-2 or, when the full backs push on, 3-5-2.

Absolutely Fabregas – Cesc has to start

The centre of the pitch is well-worked, possession is circulated, the ball is dominated, Barcelona introduce a sense of calm and control, the defence returns to reading and anticipating (rather than dealing with the roof falling in over their heads) fewer corners are conceded (vital) and Tata Martino’s side become formidable once more.

Yet something in the Argentinian seems to dare him to ignore the obvious. In their two horror defeats, to Real Sociedad in the league and then Valladolid last weekend, he has opted for three out and out strikers, left the midfield denuded – and been whupped for his troubles.

If Martino gets his selection right – Xavi, Cesc, Busquets and Iniesta must all start – then whatever the result on the night you can bet your bottom dollar that the home side will qualify.

IF his tactical statement (as he postulated on Tuesday) is ‘we are Barça, we are at home, we play 4-3-3 as a point of principal’ then City can smack their lips and approach the match with relish.

Martino has at his disposal a tiring, ageing, but nonetheless 24 karat group of footballers who are hugely stung by their recent losses and how they are being savagely criticised here in Catalunya (and Madrid) expect a reaction.

Note, please, that Barcelona limited City’s corners in the first leg. And that their marking scheme had Gerard Piqué free on the edge of the six yard box and Dani Alves paired with Alvaro Negredo.

I saw Negredo last week at the Calderon when a Brazilian-born striker, Diego Costa, relegated him to the Spain bench for the entire 90 minutes against Italy. He wasn’t chuffed. He’s found goals hard to produce in the last seven matches but is ideally shaped to end that here.

Negredo to notch a header, both teams to score but, if Martino isn’t stubborn and simply reads the runes correctly with four midfielders, Barcelona to do no worse than draw. And to proceed.

Mind you, as Kompany correctly points out, ‘football is great because it routinely provides remarkable nights when remarkable things happen’.

Stay tuned.

Hunter’s Punts

Negredo to score at anytime: 3/1
Both teams to score: 4/7
Both teams to score and Barca to win: 17/10 – or – Both teams to score and draw: 4/1

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