The referee blows his final whistle, Messi makes history as Barcelona advance to the semifinal with a 3-1 aggregate victory.

92 min: Messi's free-kick goes over the crossbar. Few moments remaining before the end.

90 min: Milan defender Mexes receives a yellow card for a clumsy challenge on Busquets on the edge of the area.

89 min: A rare Milan foray threatens Barca keeper Victor Valdes but the Barca defence eventually clears the danger.

88 min: A very poor effort from Adriano, who goes one-on-one with the keeper but shoots wide.

87 min: Barca take complete control, they dominate 60% of the possession.

86 min: Messi makes another darting run but Milan defence stops him.

84 min: Pato, who was introduced in the 70th minute, is replaced. He apparently picked up an injury, making way for striker Maxi Lopez.

82 min: Barcelona will play either Chelsea or Benfica if they advance. Chelsea, holding a 1-0 lead from the first leg, host Portuguese giants Benfica at Stamford Bridge in the second leg on Wednesday.

79 min: Eleven minutes remaining before the end. Barcelona have all but secured passage to the semis.

78 min: The third and final subtitution for Barcelona. Fabregas is replaced by Malian midfielder Seydou Keita.

76 min: Pato wastes a chance to narrow the gap after failing to control a long ball.

75 min: Barcelona defender Gerard Pique is replaced with Adriano.

74 min: A great headed clearance by Alves prevents a swerving cross from Ibrahimovic from reaching Alberto Aquilani.

73 min: Both teams ease off.

70 min: A substitution for AC Milan. Brazilian forward Pato comes on instead of Ghana midfielder Boateng.

69 min: He is released by another neat pass from Messi but he scuffs his shot wide with the goal at his mercy.

69 min: Thiago squanders a golden opportunity to score the fourth goal for Barcelona!!

66 min: Barcelona's Argentinean defender Mascherano is booked for a foul on Robinho.

63 min: The first substitution for Barcelona, Xavi is replaced by Thiago Alcantara.

61 min: A chance for Milan!! Robinho breaks clear after robbing Pique but the referee awards Barcelona a free-kick for a handball on the Brazilian forward.   

59 min: Many Milan fans are venting their frustration on social networking websites over the performance of referee Bjorn Kuipers, whom they believe has awarded Barcelona two undeserved penalties.

55 min: Barcelona close in on a place in the semifinal as they bid to become the first team to win consecutive Champions League titles.

53 min: A deflected shot by Messi loops over the defence and finds the unmarked Iniesta, who neatly controls it before beating Abbiati from close range. Milan now are facing an uphill climb to advance.

53 min: GOAAAAAAAAAAAAAAAL FOR BARCELONA!!

50 min: Milan need one goal to progress. A 2-2 draw will lift them through on the away-goal rule.

49 min: Xavi goes close to extending Barca's lead with a fine curling free-kick that goes just wide.

46 min: A penalty claim for Milan waved away by the referee. Busquets allegedly brings down Ibrahimovic.

The second half is underway.

The referee blows his half-time whistle, Barcelona 2-1 Milan. Stay tuned for the second-half coverage.

45 min: A free-kick by Milan striker Ibrahimovic strikes the wall.

44 min: Abbiati blocks another effort from Messi after some good individual work from Iniesta.

42 min: Messi converts another penalty for his 14th Champions League goal this season. He sends Abbiati the wrong way.

41 min: GOAAAAAAAAAAAAL FOR BARCELONA.

41 min: Nesta pulls the shirt of Puyol as the referee awards Barcelona another penalty. Nesta receives a yellow card.

40 min: PENALTY FOR BARCELONA!!

38 min: AC Milan are still dangerous on the break.

38 min: Fabregas tries his luck from distance but the in-form Abbiati once again rises to the occasions, saving his effort.

36 min: Barcelona are trying to regain their lead. A powerful shot from midfielder Xavi is blocked by Abbiati.

34 min: Milan now have a timely opportunity to adopt their trademark cautious strategy as a score draw would lift them through to the semifinal.

33 min: Nocerino runs onto a deft through pass from Ibrahimovic to beat the offside trap and notch home with aplomb. Milan score against the run of play!!

33 min: GOAAAAAAAAAAAAAAL FOR MILAN!!

32 min: Veteran defender Alessandro Nesta is producing an impressive displays. He intercepts many through pass from Barcelona's midfielders.

30 min: Barcelona are still laying siege to Milan's area. For how long will the Italians be able to prevent Barca from doubling their advantage?

29 min: Lionel Messi set a new Champions League record after scoring the opener. His 13th goal in one competition helped him pass the previous best of 12 goals established by himself last season and Dutchman Ruud van Nistelrooy with Manchester United in 2003.

26 min: Luca Antonini, who excelled in the first leg, is struggling to stop the threat posed by Barca's wingers, including Dani Alves who skipped past Antonini but Abbiati rushed out to thwart him.

25 min: Barca are moving the ball around smoothly. Milan's defenders are caught ball-watching as Messi controls a pass inside the area but his shot is saved by Abbiati.

22 min: Robinho side-steps Pique on the left but his short pass is blocked by the defence.

20 min: Milan's shy attacking attempts are quickly foiled by Barcelona's defenders.

18 min: Barca centre-back Carles Puyol just fails to get on the end of a corner at the far post.

16 min: Barcelona still dominate possession, keeping Milan's rearguard on their toes. It seems a second goal for Barca will follow soon.

12 min: Messi is once again proving too strong for hapless opponents. He leaves Milan defenders trailing in his wake with his dribbling skills.

11 min: Argentine wizard Messi opens the scoring. He makes no mistake from the spot with a powerful low shot that left Abbiati with no chance although the keeper dived the right way.

11 min: GOAAAAAAAAAAAAAAAAL.

10 min: Milan full-back Antonini brings down Messi as the referee immediately points to the spot.

10 min: PENALTY FOR BARCELONA!!

9 min: What an exciting Champions League clash!

7 min: Alves runs down the right, finds Fabregas whose superb first-time pass picks out the unmarked Messi, who misses the target with the goal at his mercy.

7 min: MESSI SQUANDERS A GOLDEN OPPORTUNITY TO OPEN THE SCORING

5 min: Barca immediately reply!! Messi makes one of his trademark mazy runs to elude two defenders and sends a low shot that is handled by Milan keeper Abbiati.

5 min: AC Milan do not seem very cautious! A right-wing cross is cleared by the defence.

4 min: Gerard Pique makes a great interception to deny the onrushing Zlatan Ibrahimovic. First scare for AC Milan.

3 min: Barcelona mount early pressure. Iniesta exchanges passes with Messi on the edge of the area but his mis-hit shot goes wide.

The match is underway

08:43: Both teams step onto the pitch amid a feverish atmosphere at the Nou Camp.

08:34: It remains to be seen whether Milan will be able to withstand the expected relentless pressure from the title holders, who are seeking to become the first team to win consecutive Champions League titles.

08:30: Milan coach Massimo Allegri promised before the first leg that his side would attack Barcelona but they were forced to defend in numbers for long spells to thwart the likes of Messi, Iniesta and Xavi. 

08:25: The two teams met twice in the group stage. They drew 2-2 at the Nou Camp while Barcelona claimed a 3-2 victory at the Giuseppe Meazza.

08:20: Both sides are warming up, around 25 minutes before the game starts.

08:10: AC Milan’s line-up: Abbiati, Mexes, Nesta, Abate, Antonini, Seedorf, Nocerino, Ambrosini, Boateng, Ibrahimovic, Robinho.

08:10: Barcelona’s line-up: Valdes, Alves, Pique, Puyol, Fabregas, Xavi, Iniesta, Mascherano, Busquets, Messi, Cuenca.

08:06: But Milan’s resolute defence might make life difficult for the Catalans, who struggled to break them down in the first leg despite the presence of Lionel Messi, Xavi and Andres Iniesta.

08:05: Barcelona are favourites to go through, having drawn with Milan 0-0 in the first leg in Italy.

08:00: Welcome to the live coverage of Barcelona’s clash against AC Milan in the second leg of the European Champions League quarter final at the Nou Camp.

(For more sports news and updates, follow Ahram Online Sports on Twitter: @AO Sports)##