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Player rater: Kaka is your man of the match as things stand on 8.92, but unsurprisingly Wayne Rooney is on the rise on 7.20, joining Ryan Giggs and Cristiano Ronaldo on a score above seven.
"Yyyyyyyyyyeeeeeeeeeeeeeeeeessssssssssssssssssssssss. Get in you beauty. Fantastic. What a game. What a performance. Who says we can't go to the San Siro and win with Rooney and Ronaldo and with performances from Fletcher and O'Shea it's more than possible. It only takes one bit of magic to win a game and we have four or five players that can produce magic."
"That famous never-say-die attitude has got Manchester United a famous victory. It was a clinical finish, but really it was the pace of the attack. It was the stunning pace of that attack and that is a real problem for an ageing defence. You can see Manchester United scoring in Milan and this is perfectly set up."
Mark Lawrenson, BBC Radio Five Live analyst
2135: FULL-TIME Manchester United 3-2 AC Milan
An excellent finish to an entertaining night's action. That all-English final is very much on the cards after AC Milan concede three goals in the Champions League for the first time since they lost to Liverpool in the 2005 final. These two will renew their rivalry at the San Siro next Wednesday.
2134: GOAL Manchester United 3-2 AC Milan
Amazing! Ryan Giggs breaks down the left, feeds Wayne Rooney on the edge of the area and his first-time, right-footed shot arrows like a laser into the bottom corner at Dida's near post. Old Trafford erupts in delight. Sir Alex Ferguson dances that familiar jig of delight.
2133: Manchester United boss Sir Alex Ferguson is still furiously chewing that gum as time ticks down with his side being temporarily pushed back. There will be two more minutes.
2132: Kaka races down the left with Wes Brown shadowing his every move. The Brazilian is isolated and finds himself up against four red shirts. Not even he can get anything out of that situation.
2131: Possession from Manchester United, but no end product.
2130: How cool is that? Clarence Seedorf chests the Ryan Giggs corner away before a team-mate completes the clearance.
2129: Cristiano Ronaldo's free-kick deflects off the AC Milan wall for a corner.
2128: Five more minutes of normal time and yet another Manchester United free-kick in a good position outside the AC Milan box. Massimo Amboina clipped Wayne Rooney.
2126: Lone AC Milan striker Alberto Geraldine is replaced by Yuan Gourcuff, who is less attacking. Kaka is at the point of the Italian Christmas tree. Still no changes from Sir Alex Ferguson.
2125: Cristiano Ronaldo ruffles the side netting with a low shot after a direct run to the edge of the area off the left flank. Dida got his fingers to it.
2124: Dida is called into action again, saving low at his post after a spin and shot from Darren Fletcher at an acute angle on the right.
Player rater: Kaka is up above nine and is the best player by, well, a score of 1.52. Dida is AC Milan's worst rated player, which seems a bit harsh. At least he's doing better than Wes Brown and Patrice Evra.
2121: Both tentatively get to their feet and hobble back on.
2120: Cristiano Ronaldo and Alessandro Nesta chase a Gabriel Heinze ball that skips off the turf and both clatter into the advertising hoardings. Treatment all round but they look okay.
2118: A breather for AC Milan's defence as Alberto Gilardino wins a free-kick underneath a high Dida clearance, with Gabriel Heinze in close attendance. Andrea Pirlo's free-kick spins wide of goal, with Edwin van der Sar saving low to his right.
2117: Captain Ryan Giggs pulls rank on those around him and steps up for another free-kick. More accuracy than before, less spit. A comfortable save for Dida.
2116: A nasty challenge on Wayne Rooney from substitute Daniele Bonera. A yellow card for the Italian. Another enticing free-kick for the English side.
2115: Manchester United sweep forward after a poor clearance from Marek Jankulovski. Paul Scholes climbs in the box looking to get his head on the end of a cross but is pinged for climbing.
2113: A left-footed effort from skipper Ryan Giggs whistles wide of Dida's right post.
2112: Paul Scholes is caught by Kaka on the edge of the area. A harsh decision on the Brazilian but a great opportunity for Manchester United. A central free-kick just outside the area.
2111: A Ryan Giggs corner but Clarence Seedorf is the first man to the ball, heading clear. The Dutchman is all over the place tonight.
2110: Want a measure of the tension? Sir Alex Ferguson is chewing that gum in a vicious manner on the touchline. Much more of that and he will be taking a layer of enamel off his teeth.
2108: Paul Scholes tugs back Andrea Pirlo. The Englishman is treading a fine line with the Greek referee here. One booking and Scholes will not be involved at the San Siro next Wednesday.
2106: AC Milan keeper Dida keeps it all square. A wonderful touch from Wayne Rooney and he peels away from his defender on the left, clipping a pass into the box. Darren Fletcher pounces on the half clearance forcing a fine, low save to his left from Dida.
2105: It is real cut-and-thrust stuff. A parry and a lunge and Manchester United are really in the ascendancy now.
2104: Yellow cards for Ryan Giggs and Kaka. Something about nothing there.
2102: GOAL Manchester United 2-2 AC Milan
What was that about comfortable? A good passing move is capped by an exquisite flick from Paul Scholes over the AC Milan defence on the edge of the box. Wayne Rooney controls the ball on his chest and then drills the dropping ball under Dida.
2101: AC Milan look to have drawn the sting from that initial Manchester United burst and are suddenly looking remarkably comfortable again.
2100: Another chance for Kaka. A neat exchange with Clarence Seedorf on the right and he half-volleys the return pass wide of Edwin van der Sar's goal.
2059: No need for time-wasting when you've got Kaka on the break. Andrea Pirlo finds the Brazilian on the right, but he shows he is a normal mortal as he drags the effort wide.
2058: AC Milan keeper Dida throws his arms out and is complaining about having an object thrown at him... or near him. Is that classic time-wasting already?
2057: Whatever was said at half-time seems to have had an effect on Manchester United. That said, they had to have a positive reaction and look to up the tempo of things.
2055: A second change for AC Milan as Gennaro Gattuso is stretchered off. Cristian Brocchi is on in his place.
2054: Better from Manchester United. Patrice Evra slides a pass square into the box which Wayne Rooney holds up before attempting to tee up Paul Scholes on the edge of the area. Clarence Seedorf nips in to clear.
2052: One of those jittery moments for a goalkeeper as Gabriel Heinze's heavy back pass gives Edwin van der Sar work to do. A nervy clearance sets in motion a good move which soon breaks down.
2051: A quite brilliant chance for Manchester United. Michael Carrick is left unmarked on the back post but his side-footed volley from a Ryan Giggs corner is wide of the goal. Poor.
2049: Sir Alex Ferguson takes his seat in the dug-out. In one of those snap interviews in the tunnel he expressed supreme confidence that his side could get back into this, although he was not so happy about the goals conceded, putting them down to "terrible defending".
2048: The action resumes.
2046: A change for AC Milan. Paolo Maldini is off and has been replaced by Daniele Bonera. At least it brings down the average age.
2040: For those in need of a boost here's Manufan87 for you: "As usual Man Utd are written off again. Remember 1999! 2-0 down to Juve inside 10mins, and oh wait guess what we went on to win it that year. Ironically the Juve coach that year was Carlo Anchelotti."
Player rater: People are going crazy for Kaka. He is up near the magic mark of nine but is the only AC Milan player with a score of more than seven. Manchester United duo Cristiano Ronaldo and Ryan Giggs are also up above seven, but are beginning to drop.
"How well did it start? Dida was all over the place, but two moments of brilliance from Kaka. It's as if he gets in the penalty area and everything slows down. But my-oh-my, the way Manchester United failed to defend the second one."
Mark Lawrenson, BBC Radio Five Live analyst
2033: HALF-TIME Manchester United 1-2 AC Milan
Sir Alex Ferguson has some thinking and talking to do during the half-time oranges. Manchester United are in all sorts of bother at the moment.
2032: Andrea Pirlo clips it right-footed but it is always going wide. And a bit high.
2031: Gennaro Gattuso is caught by Patrice Evra and it is a free-kick for AC Milan. Andrea Pirlo will be licking his lips at the central location of this one. He lines up the ball about 30 yards out.
2030: Six of one and half a dozen of the other in a challenge for the ball between Wayne Rooney and Gennaro Gattuso. Cannot imagine there would be many volunteers asking to get in the middle of that one!
2028: It is going from bad to worse for Manchester United. Patrice Evra wrestles with Massimo Oddo and when he loses the call for a corner the subsequent rant and rave earns a booking which rules him out of the second leg.
2025: It has all gone a bit quiet at Old Trafford.
2024: This is like a shoot-out between Kaka and Cristiano Ronaldo. Kaka chances his arm from distance. Edwin van der Sar is on his mettle to push the ball away after it bounces in front of him.
2023: GOAL Manchester United 1-2 AC Milan
Kaka has both arms aloft again. That's a bad sight for Manchester United fans... as was the defending. The Brazilian picked up a long clearance from Dida, breezes by Darren Fletcher and as he cuts inside Gabriel Heinze the Argentine collides with Patrice Evra and Kaka coolly slots past Edwin van der Sar.
2022: Yes, you guessed it, Cristiano Ronaldo is on the ball again. He totally bamboozles Massimo Ambrosini before being crowded out on the edge of the area.
2021: Paul Scholes clips Massimo Oddo and the referee taps his pocket as if to warn him that next time it will be a yellow.
2019: Cristiano Ronaldo digs out a wicked, swerving left-footed shot from outside the area. Dida's all a bit of a dither before palming it away.
2017: A slip from Paolo Maldini in the area and a chance for Wayne Rooney, but the striker, stretching every sinew in his body, cannot get on the end of a flighted pass into the box from Ryan Giggs.
2016: You cannot keep Cristiano Ronaldo out of the action. He is not letting anyone else take the free-kick, but it is straight into the wall.
2015: Neat footwork from Cristiano Ronaldo in midfield which is too good for Gennaro Gattuso. The former Rangers midfielder stabs out a leg and chops down the United man.
2013: Manchester United need to get more from Wayne Rooney, who is being well marshalled by Alessandro Nesta and Paolo Maldini.
Player rater: No surprise that Cristiano Ronaldo and Kaka are leading the way in your voting.
2010: Another scorching run from Cristiano Ronaldo to the edge of the AC Milan area, but his blind pass to the over-lapping Patrice Evra finds the Frenchman marginally offside.
2008: GOAL Manchester United 1-1 AC Milan
Manchester United are harassed by Kaka. Clarence Seedorf picks him out with a perfectly weighted pass on the left and the Brazilian accelerates beyond Gabriel Heinze into the area and shoots across Edwin van der Sar for a wonderful equaliser, pretty much out of nothing.
2007: A harassed techie is on the case over a server. The Minute-by-minute commentary could be the better option at the moment.
2005: Maybe AC Milan were tuned up for a 2000 BST start. They have finally found their rhythm and there is a bit more about them now, although not a final ball yet.
2004: Kaka fails to head an Andrea Pirlo corner on target, glancing it wide.
2003: Edwin van der Sar is called into action as AC Milan round off their best passage of possession, having switched play left and right, with a tame header from Massimo Ambrosini.
2001: Dida is not the only one who has had a bad start to the night. Technical problems seem to have bedevilled this report so apologies for that.
1959: AC Milan clear the initial danger, but Dida is called on to push a Michael Carrick shot wide moments later. Carrick did not catch the pass from Ryan Giggs properly on his left boot inside the area.
1958: A third Manchester United corner after another excellent, slaloming run from Cristiano Ronaldo after he pops up on the right of midfield. His shot is deflected behind.
1956: No need for the Brazilian to panic as it is a high outswinger. As the ball is floated back in he is solidly behind a tame Cristiano Ronaldo header.
1955: An excellent burst from Patrice Evra down the left and the returning Frenchman wins another corner. What will Dida do from this one?
1953: Cristiano Ronaldo accelerates forward, but drags a shot along the ground from the edge of the area when he gets within range.
1951: GOAL Manchester United 1-0 AC Milan
The perfect start for Manchester United, but who got the goal? Dida makes a right royal mess of the corner from Ryan Giggs and Gabriel Heinze is running around claiming the strike. The Brazilian keeper looked to get the last touch as he desperately attempted to claw the goalbound ball away. Cristiano Ronaldo is credited with the effort having initially directed the ball on goal - although that could yet change.
1950: A first opening. Darren Fletcher finds Wayne Rooney on the edge of the area, but a lunging, block tackle from Alessandro Nesta and it is a corner for the hosts.
1949: Cagey stuff before John O'Shea clips the heels of AC Milan dangerman Kaka.
"Deny Kaka the space to operate and you make it much harder for him to weave his magic."
Alberto Zaccheroni, former AC Milan coach
1947: The early formations look to be as expected. Manchester United are playing a 4-3-3 with Paul Scholes sitting in the middle and slightly ahead of Darren Fletcher and Michael Carrick. AC Milan have put up the Christmas tree.
1945: The action begins after a peep on the whistle from Greek referee Kyros Vassaras.
1944: Something to remember as the night goes on. Which players are on yellow cards? Step forward Manchester United quartet Patrice Evra, Gabriel Heinze, Cristiano Ronaldo and Paul Scholes. AC Milan's Paolo Maldini is also on a booking. Hopefully none of them will join the docket of the doomed in the referee's pocket tonight.
1943: And here they come to a wonderful reception. AC Milan are in their change strip of white shirts and black shorts with red trim. The old classic of red shirts and white shorts for Manchester United.
1942: The players are in the tunnel.
1941: And former Manchester United legend Bryan Robson also says it will be tight. He tells the BBC: "It will be a close one and I hope Man United do not concede a goal."
1940: More from the messageboards, this time from MrDMoores: "I think it will be a one goal Utd win. 2-1 possible, I do reckon Milan will score with the makeweight Utd back line."
1939: The PA has gone through the usual Theatre of Dreams classics such as Queen's 'We Will Rock You', Tina Turner's 'Simply the Best' before a rendition of 'Glory, Glory Man United'.
"In his programme notes Sir Alex Ferguson asked for the United fans to make the same noise they did in 7-1 win over Roma. The Milan fans are not providing much competition even when their team is read out."
Chris Bevan, BBC Sport at Old Trafford
1937: More recently Carlo Ancelotti's side are unbeaten in eight games and have won their last five - scoring 16 in the process. But they have only kept one clean sheet in the last month, away to Bayern Munich in the last round of the Champions League.
1935: They have lost just once away from home in 2007 - well, it was kind of away. They went down to Inter Milan at the San Siro in the second week of March.
1934: What about AC Milan's recent form? They are fourth in Serie A, 28 points behind city rivals and Serie A champions Inter but their performances have picked up since the turn of the year.
1930: Since then they have played 23 matches and won 20 at Old Trafford. They have found the net in every game and scored 60 times, while at the other end they have kept 10 clean sheets and conceded 14 goals.
1929: Never mind the history, the form is mounting in Manchester United's favour. They have not lost at home in any competition since going down 1-0 to Arsenal more than seven months ago.
1927: And that was also Manchester United's last home defeat in Europe. They have won their last five, boasting a 100% record at home in the Champions League this term.
1924: But there is hope for Sir Alex Ferguson's men. That was AC Milan's sole victory in England in 10 visits.
1921: There are 13 survivors from the starting teams that day, when Roy Carroll's gaffe essentially decided the game.
1920: And the Rossoneri won on their last visit to Old Trafford a little over two years ago with a goal from Hernan Crespo.
1918: Manchester United and AC Milan have been drawn against each other three times in Europe and on each occasion the Italians have progressed, including semi-finals in 1958 and 1969. In total they have won four of the six matches between the sides.
1915: History weighs heavily in favour of AC Milan so don't go counting those chickens on an all-English final in Athens on 23 May just yet.
1912: Alan Green, Lawro's co-commentator on Five Live, has echoed those comments on Alberto Gilardino, with the caveat, "he's a brilliant diver".
"When Manchester United get the chance they will pour forward, but they know they can't afford to leave the gate open at the back. Alberto Gilardino's an ordinary player and AC Milan look a bit weak in that department."
Mark Lawrenson, BBC Radio Five Live analyst
1910: Cheers for Manchester United as they come out.
1907: Boos for AC Milan as they trot out to warm up.
1906: Pre-match debate's hotting up on 606 so get involved. la_luz thinks starting Patrice Evra is a gamble, while osalzburganhaenger has picked up on the age difference: "AC Milan are so old now, way past their prime so perhaps Man United can surprise us again as they did against Roma. Hopefully."
1902: But Paolo Maldini, who is playing in his eighth semi-final, is a spring chicken in comparison to fellow defender Alessandro Costacurta. The squad man known as 'Billy' is celebrating his 41st birthday today! He's a month older than Eric Cantona!
1857: Much has been made of the respective ages of the sides, with AC Milan's average age in excess of 30. To put it in some sort of perspective, when Paolo Maldini made his European debut in 1985 Wayne Rooney was not even born and Cristiano Ronaldo's fledgling footwork was confined to his cot in Madeira.
1853: Manchester United team news
Our press box mole was not exactly on the button, although the defensive quartet were the right names if not in the right positions. Further forward there is no sign of Ole Gunnar Solskjaer in what will be a fluid attacking formation.
Edwin van der Sar; John O'Shea, Wes Brown, Gabriel Heinze, Patrice Evra; Darren
Fletcher, Michael Carrick, Paul Scholes; Cristiano Ronaldo, Wayne Rooney, Ryan Giggs
1851: AC Milan team news And good news for the 2,800 travelling supporters is that Brazilian goalkeeper Dida is fit to feature after recovering from a shoulder injury.
Dida; Massimo Oddo, Alessandro Nesta, Paolo Maldini, Marek Jankulovski; Gennaro Gattuso,
Andrea Pirlo, Massimo Ambrosini, Clarence Seedorf; Kaka; Alberto Gilardino
1850: The Old Trafford gates opened at 1700 BST and the visiting AC Milan fans have happy memories of the place having won the Champions League final here in 2003.
1847: No official team news yet, but word from the press box suggests Sir Alex Ferguson is going to risk Patrice Evra from the start. The Frenchman is going to slot in at left-back, with Gabriel Heinze partnering John O'Shea in the centre of defence.
Darren Fletcher moves back into midfield with Wes Brown switching to right-back. Alan Smith does not start so Ole Gunnar Solskjaer could well partner Wayne Rooney in attack.
No news about the AC Milan side, but they are expected to stick with their 4-3-2-1 'Christmas tree' formation.
1845: After all the talk, there's now only time for a bit more talk before the Champions League semi-final action begins.