The Premier League's defending champions hosted the current league leaders today at Old Trafford as Arsenal travelled to Manchester United.
Arsenal hadn't been beaten since the opening day of the season but were downed by a goal from their former striker Robin van Persie.
Read how it all unfolded in our minute-by-minute updates below.
Afternoon all! It's the blockbuster fixture of a spectacular Sunday of Premier League football as defending champions Manchester United host current leaders Arsenal at Old Trafford.
BREAKING TEAM NEWS! Former Gunner Robin van Persie is said to be out of today's game!
More news, this time from the visiting side as Per Mertesacker and Tomas Rosicky are also reportedly absent because of flu. Thomas Vermaelen and Mathieu Flamini expected to come in. We're still waiting for confirmed lineups.
SCRAP THAT! Van Persie is in the starting lineup despite all the rumours on Twitter that have been building throughout the afternoon.
UNITED XI: De Gea; Smalling, Vidic, Evans, Evra; Valencia, Jones, Carrick, Kagawa; Rooney, van Persie
UNITED SUBS: Lindegaard, Giggs, Chicharito, Nani, Cleverley, Fellaini, Januzaj
We're still waiting on the confirmed Arsenal XI, so in the meantime let's take a closer look at that United lineup. It's three changes from the last league game at Fulham as Chris Smalling, Michael Carrick and Shinji Kagawa replace Rafael, Tom Cleverley and Adnan Januzaj.
ARSENAL XI: Szczesny; Sagna, Koscielny, Vermaelen, Gibbs; Arteta, Flamini, Ramsey; Ozil, Cazorla; Giroud
As mentioned earlier, it's two changes for the Gunners as Thomas Vermaelen and Mathieu Flamini come in for the flu-ridden Mertesacker and Rosicky.
ARSENAL SUBS: Fabianski, Jenkinson, Monreal, Hayden, Gnabry, Wilshere, Bendtner
So Arsene Wenger has gone with quite a defensive lineup as Arteta and Flamini will both offer protection in front of the back four. That will allow Santi Cazorla, Mesut Ozil and in-form Aaron Ramsey the opportunity to push forward and offer lone striker Olivier Giroud plenty of support in attack.
Wenger's opposite number David Moyes has dropped Ashley Young completely from his squad after Tuesday's shocking dive in the Champions League against Real Sociedad to win a penalty. That man Van Persie struck the post with the spot kick though as the game finished goalless.
Arsenal were also in European action on Wednesday and they scored a HUGE result by beating Borussia Dortmund in Germany. Ramsey was the man with the goal as the Gunners went top of Group F.
UPDATE: Briefly away from the main match at Old Trafford, it's nearing the end in the North East where Sunderland hold a 1-0 lead over United's neighbours City. It's set to be a frantic final quarter of an hour so I recommend you open this link in a new tab to join my colleague Barney Corkhill for the closing stages.
Earlier in the midday kickoff, Newcastle caused the first upset of the day by winning 1-0 at Spurs thanks to Loic Remy's early goal. The Magpies' keeper Tim Krul was in sensational form to stop a Spurs onslaught. Read our match report here.
Back to Old Trafford and if you click this link and scroll down the page you'll be able to see all of our buildup to this big game between two of the Premier League's most successful clubs.
Fellow Mole writer Liam Apicella yesterday wrote this piece on the top five matches between the pair. The one that stands out most is that astonishing 8-2 United victory at Old Trafford in August 2011. Certainly can't see that happening again today.
This fixture last season was also an easy victory for United as they dominated the Gunners but only came through 2-1. Van Persie scored against his former club after just three minutes of his first appearance for United against Arsenal. Will he score today?
REFEREE WATCH: The man with the whistle today is Michael Oliver, who hasn't given out a single red card in games that he's officiated in all season.
If you're not following us on Instagram, you should be. Here's a collage of four men who will be important to the outcome of today's result:
UPDATE: Unbelivably, Sunderland do hold out to beat City 1-0. Match report.
Arsenal go into today's game with a lead of two points at the top of the table over Liverpool. With Chelsea drawing yesterday and Spurs and City both losing already today, a win would be MASSIVE for the Gunners.
Those shock results to the other title contenders mean that today's match is just as important for United. If they win today they will overtake City and close within five points of the Gunners.
PREDICTION TIME! It's now under 10 minutes until kickoff at Old Trafford so I best make my nailed-on prediction. I fancy a score draw and am going for 2-2. Both sides will be fairly satisfied with a point.
The final Premier League match of the weekend also kicks off at 4.10pm as Swansea host Stoke at the Liberty Stadium. If you want to follow that as well, open this link in a new tab and join Jack Prescott for updates.
Here come the two sides out of the tunnel. United are in their home colours of red, white and black while Arsenal don their rather fetching yellow and blue away kit.
Before we begin there will be a minute's silence on Remembrance Sunday to commemorate those who gave their lives for this country.
An impeccably observed minute's silence followed by a huge roar as the fans look to gee up their men on the pitch. Here we go!
KICKOFF! And we're underway at a raucous Theatre of Dreams.
United win an early corner that Van Persie swings over from the right. It's a good delivery but Sagna is there to head clear.
Giroud comes in late on Evans and the Northern Irishman is limping because of the tackle. It was nasty from Giroud but he escapes a booking as it is so early in the game.
UPDATE: Early goal at the Liberty Stadium and it's another surprise one as Stoke take the lead at Swansea. Jonathan Walters with the opener.
Back to Old Trafford where's United who are having most of the possession early on. No real chances of note so far though.
Jones nicks the ball and drives into the Arsenal half. He has little support so decides to try and go it alone but is tackled by Koscielny.
First save of the game is made by Szczesny as Rooney goes for goal from 25 yards. The pace was taken off the shot by a deflection and it was a fairly comfortable save for the Pole.
United had 66% possession in that opening 10 minutes. Just the one shot from Rooney though.
Arsenal fans obviously still haven't forgiven Van Persie for leaving them in the summer of 2012. 'Eight points clear, Robin, eight points clear!' they chant.
United aren't happy as Van Persie appears to steal the ball from Koscielny before releasing Valencia down the right but the move is stopped as Oliver blows for a foul. Very soft.
Poor from Ozil as he allows Evra to skip past him far too easily. The Frenchman's cross ricochets its way into the box before Koscielny hacks out for a throw-in. Rooney's 10th-minute effort still the only shot on goal.
The Arsenal defence stands still as Smalling's ball over the top comes to Rooney who had stayed onside. The England international's first touch isn't great though and Vermaelen is able to slide in and clear.
Absolutely nothing so far from the creative duo of Ozil and Cazorla for Arsenal, nor the red-hot Ramsey. Halfway through the opening period and the visitors haven't even had a sniff of a chance.
UPDATE: The Potters are now 2-0 up in Wales as Stephen Ireland finds the net.
A bit of action to stir the crowd as Rooney keeps the ball in on the left flank before curling over a wicked cross that Vermaelen does well to deal with Van Persie lurking.
GOAL! UNITED 1-0 ARSENAL (VAN PERSIE)
It had to be him! From the resulting corner, Rooney's curling delivery is met brilliantly by Van Persie with a flicked header that loops over Gibbs on the far post and into the corner.
YELLOW! Sagna is the first name in the book for clattering over Evra as United looked to break down the left-hand side.
Impressively, RVP has now scored in each of the last five league meetings between these two sides.
Half-chance for Giroud as a Ramsey cross from the right loops up. The centre has no pace on it and Giroud has to do it all himself but can't keep the header down.
Action in the Arsenal area as first Evra's powerful low cross is hacked clear by Koscielny before Giroud carelessly presents the ball back to United. Rooney has it in the area and he wants a penalty as the Frenchman comes back to win it off him by barging the United number 10 out of the way.
United are incorrectly awarded a corner as Sagna challenges Kagawa and the final touch is off the Japanese. From the resulting set piece, Szczesny is knocked OUT COLD in a clash of heads with Jones.
YELLOW! Jones is cautioned for the challenge and that's ever so harsh on the United man as it was a genuine attempt to head the ball. Both men have dusted themselves down and are OK to continue.
YELLOW! Flamini is booked retrospectively for a late tackle on Jones a couple of minutes ago. Arsenal are passing the ball terribly at the moment, consistently giving the ball away.
The Times journalist Matt Dickinson tweets: "Suspect we may hear lots from Wenger about the bug in camp if Arsenal don't liven up. To be fair, club said it was widespread before kickoff."
We're now into the final minute of added-on time at the end of the first half. United fully deserve their lead.
Another man is down and this time it's Vidic after being crunched by his own man De Gea making a clearing punch. This looks a bit more serious and replays show that the Serb's head was flung back rather horribly. Cleverley and Januzaj are warming up and if either come on then Jones will drop into central defence.
HALF TIME: UNITED 1-0 ARSENAL
Vidic made it to his feet and he'll be inspected over the break to see if he's fit enough to continue. The United captain looked as pale as a ghost and was spitting blood as he trundled off.
In the other game currently going on it's Swansea 0-2 Stoke at the break. Click here for our half-time summary.
STATS! In the end, Arsenal finished with 56% possession after that dominant United start. Both sides have managed just two shots on goal each. Neither of Arsenal's were on target, both of United's were.
Double Olympic gold medallist Mo Farah on Twitter: "Come on @Arsenal!!!!!"
If you're only just getting in from walking the dog or another Sunday afternoon activity and want a quick recap of the first half, read our summary here.
SNAP! Here's a shot from Getty Images of Van Persie looping that header into the far corner:
UNITED SUB: Cleverley is the man who has been chosen to replace Vidic. Jones now slots back to centre-half alongside Evans.
KICKOFF! The Gunners get the second half underway. Surely they can't play any worse in the next 45 minutes?
Rooney almost clips it inventively over the top for Kagawa but Koscielny just steals the ball in mid-air.
Better from Arsenal as Ramsey has a shooting chance on the edge of the area before Giroud is brought down by Cleverley. Free kick 30 yards out for the Gunners...
"WERHAY!" jeer the United fans as Vermaelen takes it on and skies it high and wide.
Good from Arsenal again as Ozil and Giroud look to carve out a chance among several red shirts. They tried one one-two too many and lost the ball. <--- Tongue twister!
UPDATE: Swansea have pulled one back in the other match as Wilfried Bony halves the deficit against Stoke.
The game has certainly opened up in the second period as Arsenal loosen their shackles a tad to push more numbers forward.
Rousing cheer from the Stretford End as United win a corner to put a stop to the Arsenal possession. If the Gunners don't start really threatening soon then I expect Wilshere to be brought on.
SIDE-NETTING! The visitors do have a chance as Sagna's cross is deflected through to Ozil who lashes a shot into the near side-netting with Rooney charging in to close him down.
Ramsey scored a spectacular goal against Liverpool last week but his latest long-range effort is a tame one that's simple for De Gea to bend down and claim.
CHANCE! Big, big chance for Rooney as Van Persie fails to get a ball under a control and it drops for the Englishman. He flicks the ball past the challenge of Sagna before drilling a low left-foot shot about a yard wide of the post.
ARSENAL SUB: As expected, Wilshere is sent on in place of Flamini.
There really is a sense that the 22 men on the pitch are more concerned about not making a fatal mistake rather than taking a gamble.
Cazorla finds the run of Wilshere with a perfectly-weighted through-ball. Jones is across though and wins a free kick off his England teammate when shepherding it out of play.
Valencia charges forward after a strong tackle from Van Persie on Arteta. The ball was laid in to Rooney, who tried a deft chip but timidly clipped it wide.
It's all Arsenal now as they patiently probe on the right half of the pitch before finding Giroud in the middle. The Frenchman managed to squeeze the ball out for Ramsey before Wilshere almost barged his way through to shoot but United cleared. Can the Gunners make this pressure pay?
UPDATE: Swansea have levelled it up in Wales as Nathan Dyer scores.
An opening for the visitors as Ramsey's long ball over the top looks perfect for Ozil but the German doesn't throw himself at it, instead just letting it run out of play. Odd.
CLOSE! Fantastic cross from the right by Sagna that somehow only gets a slight flick off a United head and goes out for a corner.
YELLOW! Ugly challenge from Rooney on Ramsey that earns the United number 10 a booking. Into the final quarter of an hour we go! Can Arsenal find a leveller?
They have a corner and after Koscielny's initial volley is blocked, Gibbs goes for a similarly audacious effort and it almost goes in as Van Persie deflects it but De Gea is alert. Any heavier a diversion and that was a goal.
SUBS: Ryan Giggs is on for Kagawa for his 50th appearance against Arsenal. Moments later and Wenger throws on Nicklas Bendtner for Cazorla.
YELLOW! Wilshere gets his name taken for bundling over Evra. Free kick in a good position on the left for United...
CHANCE! Van Persie's delivery to the back post finds Smalling coming in unmarked. It bounces just before the England man and he can't quite get his stooped header right and it zips wide.
ARSENAL SUB: Final throw of the dice from Wenger as he brings on Serge Gnabry for Arteta.
CHANCES! Arsenal are getting closer and closer. Giroud was just denied a shot by a superb Smalling tackle before his shot from 16 yards deflected behind.
UPDATE: Swansea have turned it around and now lead 3-2 against Stoke thanks to a second Wilfried Bony goal!
UNITED SUB: Moyes brings off goalscorer Van Persie for Fellainin, who will look to break up Arsenal's play in midfield.
Into the final five minutes we go. Arsenal are doing all of the pressing but they're still yet to really test De Gea.
Bendtner has the ball on the edge of the box but he doesn't know what to do with it and the chance of a shot is gone.
THREE minutes of time added on. It's not long for the Gunners.
BIG CHANCE! That was the chance for the Gunners. Again it's Sagna with a brilliant cross from the right that somehow goes untouched across the six-yard box. Bendtner was the closest to getting a touch on it.
UPDATE: Incredible stuff in Swansea as Stoke earn a late penalty that Charlie Adam scores. 3-3!
FULL TIME: UNITED 1-0 ARSENAL
That's it! United inflict a first defeat on Arsenal in the league since the opening day of the season.
United climb to fifth in the table and are now just five behind the table-topping Gunners.
Many thanks for joining us on Sports Mole for our live updates. We hope you enjoyed it. Stick around on site for plenty of reaction and analysis from a busy afternoon of Premier League football!