Each club was given around 39,000 tickets for this blue-riband match in a 98,000 capacity stadium – but you can expect to see red and white ribands, scarves, txapela hats, strips, banners and flags everywhere.

The Barça fans will be present, don’t worry about that. But so absolutely enormous is the hunger from the Athletic support to see their first trophy since 1984 that you can expect black market briefs to have landed in Basque hands. To the extent that, I guarantee, some Barcelona fans will have sold the tickets they won in the club lottery to Athletic fans just in order to fund a trip to Berlin for the Champions League final next Saturday.

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If you are old enough to remember how the FA used to allocate the Tartan Amy about fifteen or twenty tickets for Wembley but by the time kick off came there were at least 60,000 of us there …. like that.

• NB: If you are shading the odds based on location and the fact that Athletic have only won 18 times in 87 years of visits to the Camp Nou bear this in mind.

The concept of travelling fans in Spanish football is utterly different from the UK and Ireland. If any away team takes 1000 supporters to an away ground that’s regarded as pretty stellar. In La Liga there’s no guaranteed quota for ‘away fans’ to the extent that there is in the Premier or Champions League.

Thus if there are upwards of 50,000 Athletic fans in the Camp Nou, and I think there will be, then that utterly changes the atmosphere from any visit by Los Leones to play Barcelona in any of their home stadia.

There are a few famous occasions of mega favourites [mostly Madrid] losing the cup final in their home stadium. On their centenary in 2002 and in Jose Mourinho’s last ever Madrid game when they lost to Atleti in that dramatic 2013 Copa Final.

This is a fantastic photo of Barcelona fans’ tribute to Xavi at the Nou Camp. pic.twitter.com/QCZLf1UyN9

— Paddy Power (@paddypower) May 27, 2015

The second thing to establish is that if there has ever, in the history of this crazy sport of ours, been a support which is able to exhibit primeval levels of desire, and to transmit that sufficiently for their team to narrow the quality gap on an opponent – it’s the support of the Athletic fans.

That last trophy they won was in May 1984 against Diego Maradona‘s Barça [and it ended in Bruce Lee-Enter the Dragon style scenes between the two sets of players because of bad blood over the Butcher of Bilbao Andoni Goikoetxea-Maradona incident earlier that season] but they’ve lost their three subsequent cup ties against Barça, including the Copa Finals of 2009 and 2012, on an 8-2 aggregate.

However, believe me, it was a life-changing experience to listen to the Athletic fans at the Calderón Stadium three years ago. They’d just lost the Europa final 3-0 to Atlético and this was a gambler’s last-gasp chance at redemption.

Within what felt like the blink of an eye they were not only 3-0 down, again, but being toyed with. It was Bambi versus the Terminator. But, boy, those fans just never let up – a Phil Spectator Wall of Sound from start to finish. Part encouragement to their battered players, part pure defiance. Just monumental.

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At the end of the match when Barcelona were celebrating, Xavi and Puyol sought out an Ikurriña [Basque] flag [It’s red with a white cross superimposed on a green X] paired it with the Catalan ‘Senyera’ flag and placed them both, symbolically, in the centre circle together. A real gesture of respect.

These are the two sides which have most won La Copa and it is a regular pairing in the final too. But recent years have seen not only a resurgence of the ‘Clásico’ final but a complete alteration of Real Madrid‘s valuation of winning the domestic knockout tournament.

Thus, make no mistake, there’s a reason why this isn’t being held at the Santiago Bernabéu as Athletic wanted it to be – Florentino Pérez has got the huff.

Remember the days when not everyone could afford a football, and one dumpy kid whose parents splashed out on him every Christmas would sulk: ‘It’s my ball and if you wont’ pass to me I’m leaving, and it’s coming with me’? That’s our Florentino.

Carlo Ancelotti sacked, Rafa Benitez as good as confirmed, money to be spent, David De Gea likely to join… the last thing old Don Florentino wanted was for Basques or, worse, Catalans to be celebrating in ‘his’ stadium as they lifted the Copa up to the skies

This is the first trophy Rafa will be expected to lift when the final is played next season, in April most likely. Just watch Los Blancos clamour to hold the final in the Bernabéu or the Camp Nou then if they’ve qualified!

But… to business. If this is to be Athletic’s Copa then by far the most likely route to glory is a set play. Or the second ball off one. Barcelona are markedly better at defending them this season but lately have lost goals to both Bayern and Deportivo in this way.

Athletic have a couple of powerful weapons in this department – both Aritz Aduriz [by far their leading all-comps scorer this season, all time stat = three goals v Barcelona] and their ex-Liverpool stopper, Miki San Jose [six goals this season, none in nine v Barcelona], are aerially adept.

Bet your bottom dollar that Luis Enrique, and his tactical/strategic guru Juan Carlos Unzué will put special emphasis on Barcelona not conceding corners or free kicks in their own half.

But here’s the rub. Plenty of Ernesto Valverde‘s players have figures like: Played Barcelona 15/18/20 times Won: 1. If you want reason to believe that some kind of ‘opposition’ to Barcelona might be worth your while when you punt then it’s got to be based around the coach, Valverde.

For Athletic, in his first spell over a decade ago, for Espanyol and for Valencia he’s turned up a series of draws home and away and he won his first Catalan derby as Espanyol coach 3-1 – albeit as the Frank Rijkaard era became moribund.

Barcelona have been in ‘off’ mode since beating Atlético at the Calderón two weeks ago – valuable rest and recuperation for tired minds and bodies. But will that give them turbo-charged sharpness and power to overhaul Athletic in a blitzkreig first half …. or will it leave them just a little sluggish and vulnerable to being closed down?

Is Luis Suárez‘ hamstring fully healed?

The obvious thing to point to is that Messi loves playing Athletic – 15 goals in 22 matches against them. He doesn’t hate finals either. He’s only lost four of 17 with Barcelona and in the 22 matches those finals have entailed he’s scored 18 times plus given four goal assists.

Graham’s Bets

So, in summary. Barcelona should win, it’s far from ludicrous to suggest that Athletic might make them struggle to do so – in fact backing FCB to have to come from 1-0 down and win 2-1 doesn’t look a hopeless cause to me.

Messi, Aduriz, Piqué, San Jose and possibly [finally!] Iniesta might be worth ‘any-time’ shouts.

• Barcelona to come from behind and win – 13/2
• Barcelona to win 2-1 – 17/2
• Iniesta to score anytime – 12/5

If there was a market where you can back which fans will make more noise, throughout… back the Basques.

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