A controversial red card helped Barcelona through to the last eight of the Champions League after a 3-1 win over Arsenal on Tuesday.Lionel Messi nabbed his seventh and eighth goals of the tournament and Xavi added another for the Catalan giants, who turned around a surprise 2-1 defeat at the Emirates in their opening leg to clinch the last-16 tie 4-3 over Arsenal.Gunners boss Arsene Wenger will feel aggrieved by Robin van Persie's undeserved sending off after the Dutchman racked up a second caution, but in truth Arsenal were not much for the contest after failing to produce a single shot on target.The opening period also saw the Gunners lose goalkeeper Wojciech Szczesny to a finger injury sustained while collecting a Dani Alves free kick, although replacement custodian Manuel Almunia saved Arsenal from humiliation as Barcelona took a complete hold of the game in the final stages.Almunia had his hands full immediately after his entrance as Messi threatened often, while David Villa cut back a shot on too tight an angle and Adriano tested out the near post as Barca repeatedly pushed down the left. Van Persie, frustrated by a lack of opportunities up forward, took umbrage to Barcelona accusations that Jack Wilshere was feigning injury and remonstrated with Eric Abidal, before seeing yellow for shoving his hand in Dani Alves' face.The incident incited the Camp Nou crowd into song, and they only grew louder as Messi put the hosts ahead with a moment of sheer brilliance.Gunners captain Cesc Fabregas was at fault in the goal, attempting a clever back-heel that was easily picked off by Andres Iniesta and played forward to Messi, who bobbled the ball over the oncoming Almunia and smashed a left-footed volley into the net.The Gunners entered the dressing rooms looking downcast, but eight minutes after the break they had an unlikely equaliser.It came from Samir Nasri's corner kick, which floated in at the near post and glanced off Barca midfielder Sergio Busquets for an own goal.But their joy was short-lived as Van Persie was sent off six minutes later, referee Massimo Busacca harshly producing a second caution after the Dutchman ran on after being called offside and blasted wide of the goal.Van Persie pleaded with Buscacca, protesting that he did not hear the offside call about the noise of the Camp Nou, but to no avail.The sending off sparked Barca into action and they had soon levelled the tie at 3-3, with Iniesta playing forward and sliding a pass to Villa, whose brilliant one-touch worked Xavi into the box for a neat side-footed finish past Almunia.Two minutes later it was all over for Arsenal, Messi wresting the advantage in Barca's favour with a cool finish from the spot after Laurent Koscielny tripped up Pedro in the area.Almunia kept the Gunners in the contest with a number of fine saves, but substitute Nicklas Bendtner gave Barca a scare with a late surge into the area, but his first touch was poor and Barca goalkeeper Victor Valdes came off his line to intercept the Dane.