By FOX Sports Staff
They learnt the mistakes from the first leg and did not underestimate the Milan attack, closing in on Stephan El Shaarawy and M'baye Niang as soon as the duo manage to get the faintest of touches on the ball.
And whenever the Catalan side went on the attack, they did not obsess over passing the ball until it reached a player inside the box - Lionel Messi scored the first two goals through brilliant strikes from just outside the box.
Milan had a couple of chances but none were capitalised upon and therefore David Villa and Jordi Alba scored two goals in the second half to complete a 4-0 win on the night, and a 4-2 aggregate victory overall.
Barcelona can give themselves a pat on the back for the result and for qualifying for the quarter-finals for the sixth successive season.
FOX Sports rates the players who shone on the evening with Messi getting top marks for a sublime display that justifies his billing as the FIFA Ballon d'Or winner.
Javier Mascherano was picked ahead of captain Carles Puyol for the starting line-up and looked in complete command of the defence. He slid in on the Milan players without hesitation and readily intimidated them whenever they entered his half.
Dani Alves was also a force to be reckoned with down the right and pegged Kevin Constant back for the entire duration of the game. The Brazilian was not successful with his crosses but his determination and tenacity ensured that Milan were too busy with their defensive duties and were camped inside their box for far too long a time.
Such was their complete domination that goalkeeper Victor Valdes was also rarely called to action.
Valdes - 7 | Alves - 8 | Pique - 7.5 | Mascherano (off 77') - 8 | Alba - 8
Xavi was the captain for the night and put in a showing worthy of the armband. He made all the right passes and it was his quick one-two that allowed Messi to fire in a quick shot for opener within the first five minutes of the game.
The Spain international was also instrumental for David Villa's goal, which put Barcelona ahead in the two-legged tie, as he made a perfect pass that freed up the striker to fire on in from wide along the right.
Andres Iniesta danced with the ball and made a mockery of the efforts of the challenges thrown in his direction and the Italians even had to resort to fouls to hamper his progress.
The attackers were also helped by a diligent display by Sergio Busquets who was always ready to pressure the Milan midfielders in order to prevent them from launching their long balls with any accuracy.
Xavi - 8.5 | Iniesta - 8 | Busquets - 8
It's hard to justify just the inclusion of Messi, Villa and Pedro Rodriguez as the main attackers because the entire Barca team looked keen to get in on the action. However, these players lurked on the edge of the penalty area and pushed back the Milan defence. Furthermore, they also made runs in all sorts of directions and helped drag them out of position and open up space for the midfielders to pass into.
Messi got back to his absolute best as he did it all - he fired accurate shots from distance, got into dangerous areas, dribbled with the ball from deep past four to five defenders and even sent in through-balls to his fellow team-mates.
But it took Villa a while to get going as the Spain striker was repeatedly in an offside position in the first half. He made no mistake in the second half, though, when the ball reached him when he managed to nip behind the Milan defence and sent in a first-time shot from the right that nestled into the bottom corner.
Villa (off 74') - 8 | Messi - 9 | Pedro (off 83') - 7.5
The substitutes came on rather late and just stuck to their gameplan. Alexis Sanchez, however, was quite good with his passing and sent in a delightful long ball that presented Messi with the perfect opportunity to score a hat-trick, only for the linesman to flag the Argentinean for offside.
A short while later, the Chilean spotted Alba's run during a rapid-fire Barca counter-attack and the full-back was allowed the easiest of opportunities to net Barcelona's fourth and final goal.
Sanchez (on 74') - 7.5 | Puyol (on 77') - 7 | Adriano (on 83') - N/A
It wasn't exactly a shambolic performance by the Milan defence; instead, it would be more accurate to say that they were simply outmatched by the quality of the Barcelona attack.
Christian Abbiati did his best to stop Messi's two strikes but they were struck too accurately and beyond the reach of his outstretched hands. Philippe Mexes and Cristian Zapata also managed to put a stop to several incisive passes but Messi could still capitalise on the few yards of space given to him to score his goals.
Down the flanks, Ignazio Abate and Constant were constantly busy trying to check the progress of the Barca wingmen, which consisted any one of Pedro, Alves, Iniesta, Xavi or Alba. This meant that they could not join the attack and were therefore utterly useless to the team's cause for an away goal.
Abbiati - 6 | Mexes - 6 | Zapata - 6 | Abate - 6 | Constant - 5
The Milanese midfield could not track the positions of every Barcelona player and demonstrated poor communication, thereby allowing Messi to run amok with alarming regularity.
All they could do, really, was to concede free-kicks and it's remarkable that Kevin Prince-Boateng and Mathieu Flamini were the only midfielders to get a yellow card and no players were sent off.
Of course, they just did not have the time to run forward and help out the attackers and their long passes to El Shaarawy and Niang down the wings only met with intermittent success.
Flamini (off 75') - 6 | Boateng - 5 | Montolivo - 5 | Ambrosini (off 60') - 5
The gambit that worked for them in the first leg - pass to El Shaarawy down the left flank and expect the forward to hold up the ball until reinforcement arrived - simply did not work this time around.
El Shaarawy was constantly marked by a Barcelona player and his blend of tricks and pace only offered him a couple of chances to send in a cross down the left.
Niang was given a great deal of responsibility for an 18-year-old and therefore it would be a bit harsh to judge the striker for his inability to register too many shots. The Frenchman also had the best chance for Milan as he was quick to pounce upon a loose ball and spring the offside trap but with only Valdes to beat, his right-footed shot struck the left post in the 38th minute.
The precocious duo should take heart in the fact that they managed to trouble, even if rarely, the Barca defence with their crosses and futile attempts on goal as nowhere else in the world would a teenager and a 20-year-old be trusted with the task of penetrating the mighty Catalan defence.
Niang (off 60') - 6.5 | El Shaarawy - 7
Robinho was proving tricky for the Barcelona defenders and managed to find a yard or two of space with his clever dribbling but he could not really make an impact in the half an hour or so of his presence on the pitch. Muntari, like the other midfielders, could not keep track of the many Barca runs and rarely ventured forward to help the attack.
Bojan came on rather late to face his former side at his former home and did manage to send in a decent cross from the left that El Shaarawy nearly buried at the near post. However, any hopes of a dramatic reintroduction to the Nou Camp were shattered by a superb defensive block by Alba.
Robinho (on 60') - 6.5 | Muntari (on 60') - 6 | Bojan (on 75') - 6.5