FULL TIME! Howard Webb brings an end to Arsenal's misery on what has been a fantastic day for defending champions Manchester United. The hosts have responded to their city rival's early threat in emphatic fashion but what will this result mean for the already under pressure Arsene Wenger?
Assist Ryan Giggs
Goal Ashley Young
GOAL! Brilliant again from Ashley Young who, in a similar position to his first, produces a similar result. A magnificent curler into the far corner that means United now go top.
Smalling almost finds Hernandez to rub salt into the Gunners' wounds but the Mexican can't get a touch on a brilliant ball across the box.
Assist Patrice Evra
Penalty Goal Wayne Rooney
Aaron Ramsey's curled effort with the outside of his boot goes just past De Gea's right hand post. It's just not Arsenal's day is it?
Substitution Robin van Persie Marouane Chamakh
Substitution Theo Walcott Henri Lansbury
Interestingly, that goal makes the aggregate score of today's Manchester vs North London Premier League ties 12-3.
GOAL! Rooney makes no error has he steps up and sends Szczesny the wrong way to pass it into the bottom right of the Polish keeper's goal.
PENALTY! Evra ghosts past Djourou in the Arsenal box and Theo Walcott needlessly brings him down. Chance for Rooney's hat trick.
Exhibition stuff from United now and only a Park Ji Sung miscontrol prevents him getting in again after a Giggs through ball.
Yellow/Red Carl Jenkinson
And the day just got a little worse for the beleaguered Arsenal manager. Wayne Rooney plays Javier Hernandez behind the back four and Carl Jenkinson can do little but bring him down for a second yellow card and he's off.
That goal has done little to make the scoreline much better for Arsene Wenger. Does he have time left in the transfer window to rejuvenate this Arsenal squad?
Assist Carl Jenkinson
Goal Robin van Persie
GOAL! It's raining goals! Phil Jones heads a cross clear but as Jenkinson heads it back into the box Van Persie is onside and has time to smash it into the roof of De Gea's net.
Assist Ashley Young
Goal Ji-Sung Park
GOAL! Well if that was embarrassing then what is it now? Ashley Young finds space easily (as is becoming customary now) and plays it into the path of substitute Park Ji Sung who slides it home after just two minutes on the pitch.
This is getting embarrassing for the visitors. Wayne Rooney stands alone 20 yards out and tries a precocious chip which evades Szzcesny only to hit the bar. So unlucky.
Substitution Anderson Ryan Giggs
Substitution Nani Ji-Sung Park
Scant reward for his goal as Nani is withdrawn for Park Ji Sung. A deserved rest for the winger.
Assist Wayne Rooney
GOAL! Well if there was any doubt about where the 3 points were going 5 minutes ago it should now be well and truly dispelled. Wayne Rooney plays in Nani in the Arsenal box who inexplicably has the freedom of Old Trafford to chip coolly over Szczesny. Where was the Arsenal defence?!
Assist Ashley Young
Goal Wayne Rooney
GOAL! He's done it again and that should be that. Wayne Rooney stands over another free kick on the right hand side 20 yards out and as Szczesny takes two steps to his right the England forward spots the gap to nestle the ball in the far left hand corner of the Gunners net.
Yellow Card Johan Djourou
Substitution Francis Coquelin Alex Oxlade-Chamberlain
Francis Coquelin is replaced by another Premier League debutant, Alex Oxlade-Chamberlain.
Another miss from United and Sir Alex Ferguson will be desperate to finish this off. Anderson plays in Young in the box and Szczesny makes another fantastic low save which deflects back to the winger. He lays it back to Nani and it is a certain goal until the forward stumbles and it is cleared by Arsenal.
The next goal will be crucial here, United could end all Arsenal hope but the belief they might get from a second could swing it in their favour.
Cleverly could have finished the game there. His brilliant one two with Javier Hernandez has him alone with the keeper but his tame side-footed effort fails to beat Szczesny.
Another great opportunity for Arsenal as Arshavin gets in behind Phil Jones. The defender resists the temptation to bring the Gunners forward down and is thankful as he drags his shot wide of the left hand post.
Arsenal much more threatening this half but United's threat on the break is ever present.
Arsenal so nearly back into it. Rosicky clips a brilliant pass over the United back four onto a well timed Van Persie run. The Dutchman shoots first time on his right when he perhaps had time to control it and it is saved well by De Gea.
The Portuguese forward looking to make up for his error in some fashion by winning possession from Andrei Arshavin in his own half and releasing Wayne Rooney on the right hand side. Unfortunately for United Djourou is back to clear up the striker's attempted ball into the box.
Wasteful from Nani. He gets in behind Traore easily playing a give and go with Smalling but then chips the ball over the goal in attempting his cross. Wayne Rooney furious in the middle.
Ashley Young looking for his second goal today but Szczesny is equal to his first effort from the left and the winger pokes his second well wide.
Jenkinson looks to atone for his poor first half but his cross is blocked by Evra.
Arsenal get us underway for the second half with Van Persie and Ramsey. Can they get back into the game?
Assist Tomas Rosicky
Goal Theo Walcott
Greg Stobart from Old Trafford: "You're getting sacked in the morning!" chant the the United fans towards Arsenal boss Arsene Wenger after a scintillating half of football from the hosts here at Old Trafford. From the first minute, Sir Alex Ferguson's side played with an energy, drive and creativity that the forlorn Gunners struggled to contain. The game is as good as over despite Theo Walcott's goal on the stroke of half-time, which will again prompt questions to be asked of David de Gea, who made a wonderful penalty save earlier in the half to deny Robin van Persie. Nevertheless, Manchester is sending a real message to the rest of the Premier League today."
HALF TIME! A rampant Manchester United have laid waste to Arsenal here at Old Trafford but could that late Walcott goal put doubt in the host's minds?
GOAL! A potential second half comeback on the cards?! Rosicky plays in Theo Walcott on the right hand side of the United box who powerfully nutmegs De Gea to give Arsenal hope.
That might have been a step too far for Arsene Wenger. Wayne Rooney takes on an attempt from the halfway line but thankfully for the Gunners Szczesny is back in time to collect it.
Half time is fast approaching and Arsenal might already feel they are out of this. Devastating from Manchester United.
Assist Ashley Young
Goal Wayne Rooney
GOAL! This is fast becoming a rout. From the subsequent free kick Wayne Rooney takes one step and curls it into the very top left-hand corner of Szczesny's goal. The keeper got a fingertip to it but it was expertly placed by the England forward.
Yellow Card Carl Jenkinson
Carl Jenkinson gets away with a yellow after taking down Ashley Young on the very edge of the area. The young defender has looked nervy when called upon today.
Free kick for United at the edge of the area after Young is fouled by Djourou. Rooney dummies it to allow Nani to strike but the Portuguese winger's shot is wayward and flies over the bar.
Arsenal keep the ball well but it's all in front of Manchester United's defence and this forces Andrei Arshavin to shoot wildly over in frustration.
Substitution Danny Welbeck Javier 'Chicharito' Hernandez
Bad news for United in a first half which has seen only good. Danny Welbeck chases a long pass but pulls up short with an apparent hamstring injury. Javier Hernandez comes from the bench to make his first appearance this season for United.
Greg Stobart from Old Trafford: "In the space of a couple of minutes we have probably seen why Manchester United are the Premier League title holders and Arsenal perennial also-rans. There was little difference in the roars for David de Gea's penalty save and Ashley Young's wonderful goal, two equally important moments in this game.The Stretford End has now found its voice and are goading the the Arsenal fans by singing 'Are you Tottenham in disguise?' That will hurt."
United don't want to leave it at just two. After Robin Van Persie's effort is well saved by De Gea the hosts break brilliantly with Danny Welbeck failing to direct Rooney's cross at goal.
Arsenal fans silenced by what could be a crucial 5 minute spell.
Goal Ashley Young
GOAL! United don't mess about in punishing such wastefulness do they. Ashley Young collects a Traore clearance on the left hand side of the box and cuts inside to Coquelin easily to curl it beautifully inside the far post.
Penalty save David de Gea
Missed Penalty Robin van Persie
PENALTY SAVED! David De Gea atones for his indifferent start in a United shirt by diving to his right to palm away a weak Van Persie penalty.
Yellow Card Ashley Young
Yellow Card Jonny Evans
PENALTY! And Arsenal have their chance to get back in it. Theo Walcott is played in behind Jonny Evans and the Irishman is all over the Gunners forward and brings him down for a penalty.
Arsenal look to hit straight back but Traore's attempted cross from the left is blocked well by the sliding Smalling.
Goal Danny Welbeck
GOAL! Arsenal do well to defend a cross from wide but as Anderson collects the ball at the edge of the box he cleverly scoops it back into the area for Welbeck to nod over Szczesny. The Gunners defence just didn't do enough to challenge the young forward.
Greg Stobart from Old Trafford: "As the clouds start to gather over Old Trafford, it is beginning to look ominous for Arsenal this afternoon. United have picked up where they left off against Spurs on Monday night and are playing quick and imaginative football. The Gunners look vulnerable defensively but have done enough to show that they could be a threat going forward this afternoon."
Koscielny heads over from a Van Persie corner. Two encouraging moments for Arsenal on the counter attack which will give Arsene Wenger hope.
Arsenal with an opportunity to break but as Van Persie gets his cross away from the left hand side there is no Arsenal shirt ready to meet it.
Yellow Card Andrey Arshavin
Andrei Arshavin goes in too enthusiastically on Phil Jones with a late and high challenge and the Russian forward is lucky to only see yellow.
Brilliant passing work by Manchester United allows Cleverly to shoot when in space at the edge of the area but it is blocked well by Koscielny.
Welbeck running the channels very well again but as he slips the ball across to Ashley Young the former Villa winger is eased off the ball by Premier League debutant Francis Coquelin.
Traore involved again for Arsenal but he appears to surprise himself by skipping two successive challenges and can't get the pass away before being dispossessed at the edge of the United box.
The man who broke the deadlock against Spurs, Danny Welbeck, finds himself in space to receive an Ashley Young pass but he can onyl shoot wide on his lef foot.
A first foray into the United box for Arsenal. Traore played in behind the defence by Arshavin but he pulls it back straight on the head of Phil Jones who clears.
Wayne Rooney stings the palms of Szczesny with an ambitious effort from the left hand side of the Arsenal box. Healthy start for United.
Early chance for the hosts. Chris Smalling does well to break in behind the Gunners defence but his pull back is dragged wide by Tom Cleverly.
United have the early possession as Tom Cleverly tries to link up with Danny Welbeck but the young striker miscontrols.
Manchester United get us underway here at a packed Old Trafford.
Just minutes until kick off now and how will Arsene Wenger be feeling right now? He is asking a lot of his young side at a ground where Manchester United dropped points only once last season. Can they produce a display to silence the doubters?
Ferguson writes: "It is fair to say that United and Arsenal have had their battles both on and off the pitch, but i have never lost my respect for a man who is an accomplished manager and has erred the Gunners well. Arsene should remember that we all go through this kind of vicious bear-baiting. A few years ago, after we had gone a couple of seasons without winning the championship, the hounds were barking for me. The expectations can be amazing. They are wounded, but that could make them all the more dangerous. A game between our two clubs is always highly significant and invariably has a bearing on the destination of the title."
Greg Stobart from Old Trafford: "Manchester has already got one over north London today down at White Hart Lane and United fans are arriving here fully expecting to take three points against this wounded Arsenal side. The Gunners are still smarting from the sales of Cesc Fabregas and Samir Nasri, with the urgent need for new recruits highlighted today as youngster Francis Coquelin starts for the visitors. Arsene Wenger has come under fire from elements of the Arsenal support but Sir Alex Ferguson uses his programme notes to back a man with whom he has had many clashes down the years."
Arsenal (4-3-3): Szczesny; Jenkinson, Koscielny, Djourou, Traore; Ramsey, Coquelin, Rosicky; Walcott, Van Persie, Arshavin. Subs: Oxlade-Chamberlain, Fabianski, Chamakh, Lansbury, Miquel, Ozyakup, Sunu
Manchester United (4-4-2): De Gea; Smalling, Jones, Evans, Evra; Nani, Cleverley, Anderson, Young; Rooney, Welbeck Subs: Lindegaard, Ferdinand, Fabio, Park, Giggs, Berbatov, Chicharito
Welcome to Goal.com's live coverage of Manchester United vs Arsenal at Old Trafford. Arsenal's threadbare squad has taken a further blow with Thomas Vermaelen and Bacary Sagna ruled out today with injury. Can their young side cope with a Manchester United team unchanged from a 3-0 victory over Tottenham?
Times In BST
Live Final scheduled Suspended Cancelled Postponed