In terms of injuries, this is a strangely similar situation to the second leg at the Nou Camp last year.

Barcelona went into that game with Gerard Pique and Carles Puyol unavailable (the same as today) – whilst Arsenal were without Alex Song, and had various attacking players out injured, or half-fit. The surprise inclusion of Robin van Persie in the travelling squad, and the likelihood that Cesc Fabregas will start after a recovering from a short injury means the similarity may apply slightly less to Arsenal. They are in a stronger position than last year.

That also applies to the tie as whole, of course. Arsenal went to the Nou Camp needing to score last year – here they would be content with a 0-0. Not that anyone expects that scoreline, though, and even Arsene Wenger said yesterday that “It is a little bit of an illusion to go to Barcelona and think they will not score at all.” Arsenal will need goals.

With so many injuries, the tactical element of the build-up is dictated by replacements and how that will affect the sides’ way of playing.

Barcelona selection

The absence of both Barcelona’s first-choice centre-backs means a mini-crisis for Pep Guardiola. Last year’s combination at the back was Rafael Marquez and Gabriel Milito, but today he looks set to turn to Eric Abidal and Sergio Busuqets. Abidal has been excellent in recent weeks in Puyol’s absence, and with Arsenal missing Theo Walcott, Guardiola won’t be as worried about not having Abidal’s pace at left-back (although, in fairness, Maxwell did well in the first leg).

Busquets has filled in admirably at the back when called upon in the past few months. Often this has been as part of a back three – see last week’s win over Valencia – but he can also play in the centre of the back four. In fact, if Arsenal start van Persie, Busquets might be the perfect man to deal with him. The Dutchman will look to wander into deep positions, and Busquets will happily track him into his more natural deep midfield position. The pace of Abidal would deal with onrushing Arsenal midfielders.

Perhaps the more crucial effect is that Javier Mascherano will start as the holding midfielder. Having looked completely unsuited to Barca’s football at the start of the season, the ex-Liverpool player has played well in recent weeks. He will have a big job here – he must break up counter-attacks without picking up a booking (that completely destroys his game) and his distribution must be tidy. Busquets may step out from the back to provide a better passing option from midfield.

Arsenal selection

The absence of Alex Song – and Wenger’s statement that he won’t use Jack Wilshere as the deepest midfielder – means a choice between Abou Diaby and Denilson. Diaby would bring physicality, but his understanding with Wilshere is highly questionable. Denilson played well against Barcelona last year – his introduction in the first leg last year really helped Arsenal because he was able to retain possession – and this might be the right kind of game for him.

Fabregas looks likely to start, but van Persie is more doubtful. The choice to replace him would be between Marouane Chamakh and Nicklas Bendtner. Chamakh started the season well but has suffered from a severe loss of confidence recently – something that Bendtner is unlikely to encounter – and the Dane did fairly well at the Nou Camp last year, opening the scoring and leading the line well. He seems a more likely bet.

Unusually for Wenger, his choice of wide players may be heavily dictated by Barcelona’s full-backs. Samir Nasri did a superb job against Dani Alves in the first game – that was emphasised by the fact that when Arshavin came on and played on the left (with Nasri moving inside) Alves was suddenly much more of a force, and Arshavin’s defensive clumsiness resulted in him handballing inside the penalty area when trying to track the Brazilian. Therefore, Nasri is probably the man to start on the left.

Arshavin is very rarely deployed on the right – but in last year’s first leg at the Emirates he was, in order for Arsenal to use his technical ability without exposing him to Alves. Arsenal might be better off with Eboue on the right, however – he provides energy and pace on the break, as well as more defensive discipline.

Strategy

The tactical factors for the game are almost entirely the same as outlined in the preview for the first leg of this tie. How high Arsenal defend is a crucial factor – the high line worked well in the first game, despite conceding a couple of chances to Barcelona through runs in behind the defence. It wouldn’t be a surprise to see Arsenal defend slightly deeper, and again selection and fitness will be an issue – if Arsenal are nursing half-fit players, they won’t be able to press relentlessly.

Arsenal learnt their first leg lesson – how to press – their second leg task is how to stop Lionel Messi. The truth is that it’s impossible to stop him completely, but Arsenal played into his hands last year with their 4-3-3 system – Messi simply drifted from side to side to evade Denilson, and constantly found space.

In that review, ZM noted that a 4-2-3-1 shape would have helped Arsenal – “But the real issue must be Wenger’s decision to play a 4-1-4-1 shape, with Denilson stranded in front of the defence…with Diaby pushed forward alongside Nasri, Arsenal’s defence was left exposed. Diaby’s natural game is not as a holding midfielder, but if he had played there in a 4-2-3-1 Arsenal would have been tighter in front of their defence, and given less space to Barcelona where they really like to play.”

Arsenal using a 4-2-3-1 this season means that they’re already in a better position to stop Messi.

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