Amid the furor, the danger is that the underlying truth is lost. The decision to award Robin van Persie a second yellow card was almost inexplicable, but that should not disguise the fact that Barcelona was massively superior over the two legs. The Catalans were better for three-quarters of the first game, and for all of the second and while Arsenal can legitimately argue that losing Van Persie was a devastating blow to its morale, and perhaps prevented them adopting a more attacking game in the latter stages,it is also true that Arsene Wenger's men failed to muster a single shot in the second leg, that Lionel Messi had a legitimate goal ruled out in the first game, and that Messi should have had a penalty in the first half of the second leg.
Arsenal sat much deeper than it had in the first leg, with Van Persie very much the lone forward as Tomas Rosicky and Samir Nasri played deeper on the flanks. Nasri in particular came to appear, as Samuel Eto'o had against Barcelona in the semifinal last season, almost as an auxiliary fullback. There was a lack of dynamism to Arsenal's play, perhaps in part because the more compressed formation interrupted its usual flow and fluency, in part because Van Persie and Cesc Fabregas were clearly far from fully fit, but mainly because Barcelona drove them back. With Barcelona's fullbacks able to push forward unopposed into midfield, the game tended to be played a long way from their goal, which meant the makeshift center-back pairing of Eric Abidal and Sergio Busquets was barely tested; a shame for Arsenal, because when it did threaten them, they looked far from secure.
Barcelona wasn't at its most devastating either, wasteful in attacking positions while the deployment of Javier Mascherano in front of the back four highlighted just how good Busquets is in that position, as though he is the metronome that keeps everybody else in rhythm. The virtues of Mascherano, though, were shown in his superb last-ditch challenge to deny Nicklas Bendtner late on when it seemed Bendtner might steal an implausible away-goals win.
The accusation in Marca that Arsenal "betrayed their style" was perhaps harsh in the circumstances, but Arsene Wenger's side was so far below its usual level that the game felt anti-climactic. The injuries probably played their part in that, but Barca must take credit too for the consistency and energy of its pressing. Arsenal wasn't allowed to settle, and this remains the biggest difference between the sides. Barca presses so well that when it does lose the ball, it tends to win it back quickly, and it is so good in possession that it has to press far less than its opponents, allowing it to do so at greater intensity and for far longer.
The effect is that opponents become worn out, constantly having to hound Barca, while never being allowed easy possession itself. Jose Mourinho commonly spoke at Chelsea of the need to "rest with the ball;" against Barcelona it's impossible. There can at times be something almost attritional about the way Barca plays, in that it forces opponents into errors, such as the misplaced Fabregas backheel that led to Messi's opening goal, or Laurent Koscielny's clumsy challenge that led to the penalty for the third. Counter-intuitively, there is something highly pragmatic about its short-passing, possession-based approach.
Roma, to its credit, at least tried something different, trying to counter Shakhtar's 4-2-3-1 with a 4-3-3, with Mirko Vucinic to the left of Marco Boriello and Rodrigo Taddei to the right, in front of a midfield three of Simone Perrotta, Daniele De Rossi and David Pizarro. The intention, presumably, was to hem in the Shakhtar forwards and prevent them linking up with the wide players in the attacking-midfield trident. Perrotta was relatively successful in that, and Razvan Rat, the Shakhtar left back, was comparatively restrained. Dario Srna, though, played as he always does, as much a winger tracking back as a fullback pushing forwards.
By focusing on the flanks, though, Roma neglected the center, where Tomas Hubschman and, particularly, Henrik Mkhitaryan, who has slightly surprising emerged as a creative replacement for Fernandinho, who suffered a horrible broken leg earlier in the season, provide a far more progressive curtain than is common. Both completed over 80 percent of their passes and that wasn't a result, as such statistics often are for defensively-minded players, of them racking up the percentage with a series of short sideways balls.
Roma had arguably been the better side when Willian put Shakhtar ahead, and had Boriello converted his penalty and Philippe Mexes not been sent off, it might have mounted a more significant challenge. As it was Shakhtar was able to control the game, and exploit the space left by the red card: an intelligent, unflustered performance from a side that, fresh after a winter break, may be more serious contenders than is generally accepted.
It was a game for tearing up the stereotypes. AC Milan was far more progressive and purposeful than Serie A teams have been in European competition this season; Tottenham, having found itself under pressure early on, defied those who said it could play only attacking football and defended excellently in the second half. Whether the relative comfort of its progress was down to Milan, unused to playing at such a high tempo, running out of steam or the excellence of its organization is hard to say, but it's probably fair to say it was a bit of each.
The early stages saw Tottenham unable to control midfield as it had in the first half of the first leg. That had always been the danger, that its 4-4-1-1, although dangerous wide, wouldn't win enough ball against Milan's 4-3-1-2, with its numeric advantage in the center, to feed the wingers. In that, the use of more creative players in midfield -- Clarence Seedorf, Mathieu Flamini and Kevin Prince Boateng, as opposed to Rino Gattuso, Thiago Silva and Flamini -- made Milan more of a handful because it had passers to retain possession, rather than scrappers left chasing to try to win it back. Seedorf, in particular, added an element of calm and class that had been missing in the first leg. Milan also made a conscious effort to double up on Aaron Lennon, more naturally a wide player than Steven Pienaar, with Boateng funneling back to support Marek Jankulovski.
After halftime, Spurs seemed far more content to sit deep, absorb pressure as it could -- Michael Dawson and William Gallas were magnificent in central defense, but Sandro was even better at the back of the midfield -- which also made it more dangerous on the counterattack, as Lennon tended to have space to run into, and Jankulovski tired. For a man who professes bluff disdain whenever tactics are mentioned, Harry Redknapp is a master at making changes that turn a game in his side's favor.
Jonathan Wilson is the author of Inverting the Pyramid; Behind the Curtain; Sunderland: A Club Transformed; and The Anatomy of England.