Manchester United won away for the first time this season when they beat Arsenal 2-1 at the Emirates Stadium on Saturday to climb to fourth in the Premier League table.
An own goal from Kieran Gibbs in the 56th minute and a decisive 85th minute strike from Wayne Rooney after a swift counter-attack sent Arsenal to their first home league defeat since Aston Villa beat them on the opening day of last season.
Arsenal pulled a goal back in the fifth minute of stoppage time when Olivier Giroud, on as substitute after a three-month injury layoff, beat goalkeeper David De Gea with a long range shot moments after Angel Di Maria missed a golden opportunity to put United 3-0 up.
Earlier, Chelsea beat West Bromwich Albion 2-0 to stay top of the table as they stretched their unbeaten run from the start of the season to 18 matches in all competitions.
They have 32 points from 12 matches, followed by Southampton, who play at Aston Villa on Monday, on 25 from 11 and champions Manchester City on 24 points from 12.
City stayed in touch with Chelsea when they came from behind to beat Swansea City 2-1 at the Etihad Stadium with Stevan Jovetic and Yaya Toure finding the target.
United are fourth on 19 points, ahead of Newcastle United on goal difference after Newcastle beat Queens Park Rangers 1-0, with Arsenal having fallen from sixth to eighth on 17 points.
Arsenal will rue the umpteen scoring chances as they went down to Manchester United by the odd goal in three in the Premier League encounter at the Emirates Stadium on Saturday night.
With this win Van Gaal's side move up to fourth in the standings, while Wenger's boys are in eighth position.
Arsenal should have nailed the match in the first half itself but Danny Welbeck, Wilshere, Chamberlain were either off target or denied by some superb goalkeeping by De Gea.
But as they say fortune favours the brave and that's what happened with United as a lucky goal from a deflection by Arsenal defender Kieran Gibbs into his own net followed by a Wayne Rooney classic sealed it for Van Gaal's side.
Franck Giroud's late goal only revived Arenal's hopes of atleast a draw but it was a case of too little too late.
United 2 (Gibbs og 56' Rooney 84') Arsenal 1 (Giroud 90+5)
United 2 (Gibbs og 56' Rooney 84') Arsenal 1 (Giroud 90+5)
90+5 GOAL! Giroud scores a fantastic goal to finally breach De Gea's citadel.
90+3@ Di Maria could have added his name to the scorer's list but after some good work by Rooney the Argentinian made a mess by dinking one over goalkeeper Martinez only to miss the net.
90" Eight minutes of extra time added.
United 2 (Gibbs og 56' Rooney 84') Arsenal 0
80" Arsenal are doing everything but score and with only 10 minutes left they seem to be running out of ideas.
76" Arsenal too make a change with Giroud coming in for Ramsey.
74" Van Persie is replaced by James Wilson.
73" Great tackle from Smalling to deny Welbeck a closer look at goal.
70" Sanchez sends his free-kick way over the top barely testing De Gea.
67" De Gea looks impregnable today as Arsenal try hard to beat him. Cazorla has a powerful right footer from just outside the box but the Spanish goalkeeper is at hand to stop it.
65" The match is evenly poised at this juncture with both teams having the share of the ball.
YELLOW! Cazorla having just come in has been cautioned.
61" What a match De Gea is having, denying Sanchez a sure goal for an equaliser.
58" Szcsesny is out and Damian Martinez comes on.
United 1 (Gibbs og 56') Arsenal 0
50" There is chaos once again in the United camp as a poor Fellaini pass goes to Chamberlain and he puts Wilshere but the latter stretches too much and seems to have pulled a hamstring. He is limping and is likely to be replaced.
48" Welbeck makes a solo run but De Gea stands like a rock in front of him.
47" Good footwork from Chamberlain on the right and flicks it to Chambers who misses after stretching full length.
46" Blackett's back pass put De Gea under pressure who clears in a huff.
United 0 Arsenal 0
45+2" The whistle goes off.
45" Play has moved into two minutes of injury time.
42" Welbeck backheels but misses the target after Ramsey does well to bring the ball back from a corner kick.
40" United seem to have shaken off some early nerves and have got more ball possession now earning three corners in a five-minute spell.
37" Di Maria makes a superb Messi-like run from the halfway and finds Rooney with a deft pass but thanks to Chambers who sticks his foot out to save the England striker's shot.
35" That was pretty cloe from United. Fellaini and Valencia engage in a passing bout and then find Di Maria, his curling left footer goes wide past the outstretched hands of Szczesny.
33" Sanchez comes up with a futile shot which De Gea dives to his right to collect.
32" Szczesny make his first contact with the ball but thats an easy collection from a Rooney free-kick.
28" Wilshere and Fellaini get into a scuffle for no good reason. Frustration mounting here as Arsenal despite dominating are yet to score while United have yet to make any headway in the game.
25" Arsenal are squandering too many chances. Mertesacker gets his legs entangled when going for a shot in the box and Sanchez overdoes with the ball and kicks wide.
22" Another golden oppoirtunity goes abegging for Arsenal as Chamberlain is slow in turning around De Gea and that give the goalkeeper time to block his shot.
20" United have their first real look at the Arsenal goal but Rooney boots his free-kick well over the crosspiece to the jeers from the crowd.
16" Shaw limps off and Ashley Young is in. Nothing going right for United.
14" Oh no Arsenal are all over United and should have been up by atleast two goals. United are all panicky and Wilshere should have capitalised but with only De Gea at his mercy and no defender on his heels and all the time in the world he shoots straight into the keeper. Hope the Gunners are not made to rue this chance.
12" Wilshere's top of the box left footer is collected by De Gea. A few seconds later De Gea is tested again by Welbeck but it's a poor shot.
10" The Arsenal forwardline looks determined pushing United on the back foot. Chamberlain, Welbeck, Chambers and Ramsey are playing havoc in the United territory.
8" Livewire Oxlade-Chamberlain gets the better of Rooney and crosses for Welbeck whose header goes over.
7" Luke Shaw is limping on the sidelines and there is concern on Van Gaal's face.
4" There is a loud roar at the Emirates Stadium as Ramsey and Chambers work out a nice move on the right flank and feed Welbeck who is in position to score but De Gea blocks his angle and parries it away for a corner.
3" Luke Shaw intercepts a nice pass and makes a dangerous 25-yard run but his pass to Van Persie has the striker in a off-side position.
Arsene Wenger has taken a gamble and is playing the injured Danny Welbeck against his former club Manchester United. Can it prove a masterstroke only time will tell as we are just five minutes away from kick-off.
Michael Owen has predicted a 2-1 win for United.
Arsenal: Szczesny, Chambers, Mertesacker, Monreal, Gibbs, Arteta, Ramsey, Sanchez, Wilshere, Oxlade-Chamberlain, Welbeck. Subs: Rosicky, Podolski, Giroud, Cazorla, Flamini, Martinez, Bellerin.
Man Utd: De Gea, Smalling, McNair, Blackett, Shaw, Carrick, Valencia, Fellaini, Rooney, Di Maria, van Persie. Subs: Mata, Januzaj, Lindegaard, Young, Ander Herrera, Fletcher, Wilson.
Referee: Mike Dean (Wirral)
@ManUtd: DID YOU KNOW? ManUtd have lost just 2 of their last 18 games against Arsenal!
@Arsenal : Sanchez has opened scoring more times than any other Premier League player this season. How many times? 5.
This is the line-up in the training: De Gea | Smalling McNair Blackett | Valencia Carrick Fellaini Di Maria Young | Rooney Rv from Manchester United
Man Utd boss Louis van Gaal throws the first one-two for us, with a praise of Arsenal's style of play, on BBC, and then with the Telegraph, he insists Danny Welbeck was only good enough to be a Man Utd substitute!
Meanwhile, the peopl@ManUtdChannel tweet: "LVG set up a 3-5-2 in training yesterday: DDG, Valencia, Smalling, McNair, Blackett, Young, Carrick, Fellaini, Di Maria, Rooney, RVP".
Robbie Savage on Danny Welbeck for his BBC column: "It would not surprise me if Welbeck got the decisive goal in a game that I expect Arsenal to win."
And the early pre-match Twitter narrative is unfolding quite nicely.
Ángel Di María: Has created more clear-cut chances (23) than any other player in Europe’s top 5 leagues in 2014... this from whoscored.com
Lionel Messi could have been an Arsenal player if Arsene Wenger had got his way, courtesy BBC, and...
Joke of the Day!
@GNev2 What did you tell Jack Wilshere when you pulled his earphones out ?” Play well tonight but not v United Sat!
The countdown begins, and given that these two English Premier League giants are fighting to stay alive - which means a Top 4 finish - this battle needs all the countdown it can take
Michael Owen is still going with Man Utd to win?
What are you going with? Let us know as we bring you the latest.
Wenger to play Welbeck?
Arsene Wenger says Arsenal striker Danny Welbeck has been playing with a point to prove as he prepares for his first reunion with former club Manchester United on Saturday.
Welbeck has impressed for the Gunners since his £16 million ($25.1 million, 20 million euros) transfer deadline day switch from United.
The England international's five goals in 12 appearances have gone some way to silencing the critics, including United boss Louis van Gaal, who said Welbeck wasn't up to the standard required at Old Trafford.
Arsenal manager Wenger knows he has benefitted from Welbeck's determination to show he can make it at the highest level and he expects the forward, a boyhood United fan who had been at the club for 11 years, to be fully motivated when United come to the Emirates Stadium this weekend.
"You can take every challenge in a positive way and that is what Danny did," Wenger said.
"You have to understand Louis van Gaal did not have Welbeck under his command for a long time and it is always very difficult to know the players well when you see them for three or four weeks.
"Wayne Rooney and Robin van Persie have an exceptional goalscoring record - he had two quality players in front of him, so what he needed was a chance.
"What is important is that the player makes a good career and has a good opportunity."
United, like Arsenal languishing well behind leaders Chelsea after a spluttering start, received a fresh blow during the international break when Dutch midfielder Daley Blind sustained a knee ligament injury likely to sideline him for several weeks
But although they face ongoing injury problems in defence, goalkeeper David de Gea and midfielders Michael Carrick and Angel di Maria should all be fit to face Arsenal despite sustaining knocks on international duty.
The season may be only 11 games old, but complacency and rank misfortune already seem the only factors capable of preventing Chelsea from romping to a first league title since 2010.
A 2-1 win at Liverpool enabled Jose Mourinho's side to open up an eight-point lead over reigning champions Manchester City prior to the international window, while Arsenal, United and Liverpool are even further back.
"The win at Anfield was really important because it was a really difficult game and we knew it was important for the future," said Chelsea left-back Filipe Luis during a fan event at Stamford Bridge this week.
Chelsea host West Bromwich Albion on Saturday and will hope to see top scorer Diego Costa firing on all cylinders after he was left out of the Spain squad to rest his troublesome hamstrings.
The only team who have threatened to keep pace with Chelsea are Southampton, who trail the leaders by four points ahead of their trip to Aston Villa in the Monday night game.
Champions City will look to drag themselves out of a damaging rut when they host Swansea on Saturday, having won only one of their last six matches in all competitions.
Manuel Pellegrini's side are on the brink of elimination in the Champions League ahead of Tuesday's home game with Bayern Munich, but have at least been able to rely on the form of Sergio Aguero.
The Argentine sharp-shooter scored his 11th and 12th league goals of the season in City's 2-2 draw at Queens Park Rangers a fortnight ago and appears to have overcome the injury problems that bedevilled him last term.
Another team in desperate need of an upturn in fortunes are Liverpool, who lie in 11th place, 15 points behind Chelsea, after three games without a victory.
On Sunday, Brendan Rodgers's side play Crystal Palace at Selhurst Park, scene of their crushing late-season capitulation last May, when they effectively gifted City the title by letting a 3-0 lead slip to draw 3-3.
Liverpool's woes have been compounded by the news that striker Daniel Sturridge could be out until the new year after aggravating a thigh injury.
Saturday (1500 GMT unless otherwise stated):
Arsenal v Manchester United (1730 GMT), Chelsea v West Bromwich Albion, Everton v West Ham United, Leicester City v Sunderland, Manchester City v Swansea City, Newcastle United v Queens Park Rangers, Stoke City v Burnley
Crystal Palace v Liverpool (1330 GMT), Hull City v Tottenham Hotspur (1600 GMT)
Aston Villa v Southampton (2000 GMT)