FC Barcelona produced a performance full of power and intelligence to defeat AC Milan and progress to the semi-finals for the fifth successive season.
Two penalties from Lionel Messi, the first his 50th goal in this competition which set a new scoring mark for a UEFA Champions League season, had Barcelona in front at half-time despite a first-class equaliser from Antonio Nocerino. Andrés Iniesta extended the hosts' advantage early in the second period and the holders held on in some comfort, only Gerard Piqué limping off in the second half souring their night.
Messi's first goal, his 13th of this season's competition, came from the spot in the 11th minute but its creation was down to his intelligence and work rate. Philippe Mexès dallied in possession and Messi raced to rob him, bursting forward before unselfishly cutting the ball back. The Milan defence scrambled to recover but as Messi and Luca Antonini contested the loose ball the Italian brought down his opponent, who picked himself up to beat Christian Abbiati with the spot kick.
That goal surpassed the previous 12-goal best for a UEFA Champions League season, set by Ruud van Nistelrooy in 2002/03 and equalled by Messi himself last season, although it might have arrived even earlier. Six minutes in Daniel Alves sent in a low cross, Cesc Fàbregas produced a sweet flick but Messi unusually steered his point-blank shot wide with his right foot.
Milan were being caught in possession, the ultimate sin at the Camp Nou, but while Abbiati continued to save at the end of a flood of Barça moves there was hope. On 32 minutes hope turned into tangible reward; contrary to Piqué's regular warnings, Zlatan Ibrahimović was allowed to bring the ball down and turn. The Sweden striker slid a sublime pass into the overlapping Nocerino, who slotted in a low shot without breaking stride.
The statistic that Milan have won six out of the eight ties in which they drew the first leg 0-0 at home suddenly seemed worryingly relevant for Barça. What did not change was the sparkle of their football, Abbiati turning a fierce Xavi shot behind after a slick one-two with Fàbregas.
The twist came four minutes before half-time; as Xavi's corner curled in, Nesta tugged Sergio Busquets to the ground to give Barcelona a second penalty. Messi changed the direction of his effort but found the net just as effectively.
Even though Barcelona continued to make subtle mistakes which denied them a definitive advantage, the second half was only eight minutes old when they breached Milan's defence again to effectively settle the tie. Messi's deflected shot looped kindly into the path of Iniesta, who controlled with his left foot and beat Abbiati with his right to put Barça in charge.
Josep Guardiola's team used all their savvy and skill to control the remainder of the match and even in the late stages Adriano was clean through but dragged a shot wide. Perhaps the semi-final, against Chelsea FC or SL Benfica, will demand more clinical work.