BBC Sport - Barcelona 4-0 AC Milan Barcelona made Champions League history by overturning a two goal deficit without an away strike to knock out AC Milan and reach the quarter-finals. The Catalans wasted no time and scored in the fifth minute when Lionel Messi expertly curled in from 20-yards. The Argentine soon levelled the tie as he took advantage of space on the edge of the area with a low drive. David Villa put Barca ahead after being found by Xavi before Jordi Alba sealed the win in injury time. Barca v AC Milan at a glance No side had ever come back from a two-goal first-leg defeat without the benefit of an away goal before Barcelona's result AC Milan's 4-0 defeat equalled their heaviest ever loss in the competition Barcelona are now undefeated in 20 home games in the Champions League For all Milan's excellence in the round of 16 opener, Barcelona had laboured towards a 2-0 defeat in which they uncharacteristically registered only one shot on target. But their usual zip returned on the vast Nou Camp pitch from kick-off as they started at high tempo. This intensity was rewarded immediately as Messi played a neat one-two with Xavi and finished into the top corner with goalkeeper Christian Abbiati rooted to the spot. The goal was the world player of the year's 52nd of the season, but his first in open play in 10 meetings with Italian sides. At the San Siro, Milan's tight, disciplined display saw their centre midfielders cover a deep-lying and compact defence which left no gaps for their opponents to run through. Critically, this support was not present on Tuesday as Barcelona were granted space on the edge of the penalty area. The Italians survived two penalty shouts and a poor Messi header, but the tie's key moments arrived with just over five minutes of the first half remaining. First, striker M'Baye Niang struck the base of the post after racing through on goal following a swift counter-attack from a Barcelona corner. If the France Under-21s international had managed to get an away goal, their opponents would have had to find the back of the net at least three more times to proceed. Instead, Milan's advantage from the first leg was wiped out moments later as Messi fizzed in an unstoppable shot from 20-yards after Massimo Ambrosini lost possession. Barcelona continued on the front foot after the interval and went ahead on aggregate for the first time when Villa finished clinically after he was picked out in the box by Xavi. The goal owed much to left-back Kevin Constant's rash attempt to intercept the pass before it reached the striker. The visitors now knew they had to score to stand any chance of progression and head coach Massimiliano Allegri brought on former Manchester City striker Robinho. This change nearly produced the breakthrough the Serie A side were looking for. Barcelona youth product and fellow substitute Bojan Krkic put in a low centre that Robinho seemed certain to convert before defender Jordi Alba dived across to block the shot. Barcelona refused to sit back on their lead and a wonderful counter from a Milan free-kick in injury-time saw Alba further excel at the other end of the pitch when he raced on to Alexis Sanchez's cross to slot past Abbiati to raise the Nou Camp crowd to their feet. Barcelona 01 Valdes 02 Alves 03 Pique 18 Alba 06 Xavi 08 Iniesta 10 Messi 14 Mascherano (Puyol - 77') 16 Busquets 07 Villa (Sanchez - 74') 17 Pedro Booked (Adriano Correia - 83') 13 Pinto 05 Puyol 21 Adriano Correia 04 Fabregas 25 Song 09 Sanchez 37 Cristian Tello AC Milan 32 Abbiati 05 Mexes Booked 17 Zapata 10 Boateng Booked 16 Flamini Booked (Bojan - 75') 18 Montolivo 20 Abate 21 Constant 23 Ambrosini (Muntari - 60') 92 El Shaarawy 19 Niang (Robinho - 60') 01 Amelia 02 De Sciglio 25 Bonera 04 Muntari 08 Nocerino 07 Robinho 22 Bojan Ref: V Kassai