For individual match reports, statistics, player ratings and key moments from each game, click on the headers below.
The pressure had been building on Arsene Wenger ahead of this game and the visit of West Brom was probably a team he'd like to have avoided at the weekend - a side above the Gunners in the league on a fraction of the budget. But Arsenal claimed the points to renew belief that a top-four finish is once again within their grasp.
That came thanks to two penalties for the home side, one of which was particularly dubious as Santi Cazorla went down despite Steven Reid making no contact with him. It was extremely harsh on the Baggies who have now lost three on the bounce and are in danger of fading back into mid-table. But Wenger will surely take the victories however they come right now.
Villa's goalless encounter at home to Stoke was certainly not one for the purists as both defences stood out in a game void of any clear opportunities. Paul Lambert's 3-5-2 formation worked a treat until the introduction of Darren Bent midway through the second half and the switch to a more conventional 4-4-2 - which didn't quite work so well.
Perhaps Villa supporters need to start showing more faith in the Scot. He clearly has his reasons for not wanting to start with the England striker on a regular basis and this match showed us exactly why. Without him, Villa were bright, alert and full of energy with Christian Benteke a handful - but with him, they lacked a cutting edge and lost their shape and confidence.
The hosts were dominant in the opening 45 minutes keeping possession well and creating chances. The Holte Enders thoroughly enjoyed watching this young team grow in confidence. Ciaran Clark's tackle on Glenn Whelan ignited the contest on the stroke of half-time and Tony Pulis was careful with his words after the game, but said in no uncertain terms that the Villa man should have been shown a straight red. Although tempers frayed in the second period, things soon settled down with neither 'keeper making a save of any real note.
Stoke have now kept eight clean sheets in the Premier League and with a solid partnership of Robert Huth and Ryan Shawcross at the back, it's little wonder they don't concede. The Potters are up to ninth in the standings and have lost just three times this season.
Although they're a tough nut to crack, Pulis will wonder where his goals are coming from. Between Kenwyne Jones, Cameron Jerome and Peter Crouch, City don't look like scoring a goal. With Michael Owen consistently out injured, maybe Pulis will have to turn his attentions to the January transfer window.
The weather has turned chillier over the last week or so, and it certainly looks like a bleak midwinter is in the offing for Reading on the evidence of their defeat to Southampton.
Given the number of chances they created against Man United a week earlier, the Royals fans who travelled to the south coast would have expected more than the anodyne fare they were served up. Hal Robson-Kanu's header against the post at the end of the first half proved to be their best chance, but they were still in it at the end despite Southampton's dominance of possession.
Nigel Adkins' side have pulled their socks up after a slow start to the season, and have lost just one in their last seven at home. Home form will be the key to whether they stay in the Premier League, but the signs are promising if they can deal with the teams around them in the manner they did with Reading.
Jason Puncheon had a day to remember and deserved his goal, but the worry will be whether Southampton can hang on to Adam Lallana in January. Alan Pardew is said to be keen on reuniting with the midfielder at Newcastle, and on the evidence of his display before his injury on Saturday, Saints fans may have to brace themselves for a bid.
Rafa Benitez enjoyed his best day since becoming Chelsea manager as Fernando Torres inspired a 3-1 victory over Sunderland, leaving onlookers to wonder whether the Blues could still get back in the title race once they return from a December sojourn to Japan for the Club World Cup.
The Blues have certainly not looked like the best team in the world over the past few weeks but there were signs of the early-season sparkle returning as Juan Mata, Eden Hazard and, perhaps most significantly, Torres, all impressed.
Benitez has insisted he is the man to get the best out of Torres and after netting his first, a wonderful first-time volley, the striker looked full of confidence. He had no intention of letting David Luiz take the ball off him when Chelsea won their penalty and was only denied a hat-trick by the width of the post.
Luiz also impressed defensively and Benitez showed an attacking mindset when Oriol Romeu had to go off injured early on, bringing on the more creative Oscar.
It was not all one-way traffic and Sunderland carved out a number of good chances, with Petr Cech forced to make several solid saves. That will be little comfort for Martin O'Neill, though, whose team are now in the relegation zone following results elsewhere.
The Black Cats manager is sure to remain under pressure until their situation improves and the next few weeks could be crucial, with games against fellow strugglers Reading and Southampton as well as Manchester United and Manchester City.
Swansea obviously paid the price for their slow start but the reason appeared to be the absence of Leon Britton in central midfield. The 30-year-old makes things tick for his side and Michael Laudrup will want to have his key man back as soon as possible.
Laudrup's decision to restore Danny Graham to his starting XI for the first time since the beginning of October did not really work. The striker's return meant Michu dropped deep in the first half. Will Laudrup continue with the selection in Wednesday's Capital One Cup game against Middlesbrough or next weekend's trip to Tottenham Hotspur?Swansea's abysmal first-half performance should not take away from Norwich. Chris Hughton has his side organised and disciplined. The manner in which they picked off Swansea at set-pieces was clinical and clearly well researched and pre-planned.
Harry Redknapp is trying to put a positive spin on QPR's recent results. A 2-2 draw here means they are three unbeaten under the new manager but all three games have been draws and the Hoops are already cut adrift at the foot of the table.
There were some encouraging signs for the bottom club at the DW Stadium on Saturday and they began brightly. But confidence remains fragile as you would expect of a team that is yet to win a league game this season and there was never any real conviction that they would hold on for the win here.
Redknapp looks content to sideline some of the mercurial talent at Loftus Road in favour of honest professionals such as Shaun Derry, who returned to the starting line-up in favour of Esteban Granero, but with the need for inspiration now desperate it seems unlikely that graft will be enough to ensure survival.
There are so many things to talk about after this classic Manchester derby but first the simple fact that Manchester United are six points clear in the Premier League title race should be pointed out first.
That doesn't end the battle for top spot by a long way but the Red Devils are now the team with the edge and certainly the one that will be smiling most this week.
Sir Alex Ferguson has plenty of positives to take from the win and one of the biggest has to be the fantastic performance of goalkeeper David De Gea.
The Spaniard's sensational double save will be remembered for some time but there was much more to like about a calm performance.
Manchester City fans will have one main question - why didn't Carlos Tevez start?
The forward has been redeeming himself with some great displays this season and currently offers a more consistent threat than the very disappointing Mario Balotelli.
Tevez changed the game when he was introduced but ultimately couldn't help City take anything from Super Sunday as Robin van Persie had the last word.
Well, it turned out to be the late, late show at Goodison Park as Everton fought back from a goal down to secure a dramatic 2-1 win and it was thoroughly deserved on the balance of play.
The Toffees have not lost at home this season and they had to show all their fighting spirit, which has been instilled in them by their manager David Moyes to seal a dramatic three points which moved them above their opponents in the table. And it looks as though these clubs - along with Arsenal - will be battling it out until the end of the season for fourth position and a route into the Champions League.
Andre Villas-Boas will be glad he doesn't have to put out his strongest side on a Thursday night's for quite a while because his players looked exhausted with ten minutes remaining. If Premier League games had ended at 80 minutes this season, Spurs would be top and maybe AVB should have looked into that crucial statistic before bringing off the towering presence of Mousa Dembele.
Without Gareth Bale in the line-up, the north Londoners were void of ideas and the balance of the team didn't look quite right for long periods. Even the usually bright and alert Jermain Defoe seemed out of sorts.
There was one bright spot though. The performance of Hugo Lloris between the sticks was excellent. The France No.1 showing us exactly why Spurs paid £12million for him on deadline day and why he deserves to be getting a run in the side.
With the visit of Swansea and Stoke to White Hart Lane to come in the next couple of weeks, AVB will be targeting maximum points to keep the heat on the Merseysiders. On the flip side, there were far more positives to take away for the hosts from this game and of course the display of three players in particular - Steven Pienaar, Marouane Fellaini and Nikica Jelavic. And the Three Amigos will have to be at their best for away trips to Stoke and West Ham next.
With Luis Suarez suspended, Liverpool fans must have felt quite apprehensive ahead of their clash with West Ham when Brendan Rodgers' team sheet failed to include a single striker in the starting eleven.
With Jonjo Shelvey playing as a makeshift attacker, things started incredibly well for the Reds when Glen Johnson's marvellous solo goal gifted the Reds the lead.
It didn't take the Hammers long to turn the game on its head though, in fact it took them just over 30 minutes, as a Mark Noble penalty and Steven Gerrard own goal saw West Ham go in 2-1 up at the break.
Mohamed Diame was having another colossal game in West Ham colours, and his departure due to a hamstring injury proved the catalyst for what turned into an extremely impressive Liverpool comeback.
Diame, linked with a move elsewhere in January, was pulling the strings in defence and attack, and Liverpool looked uninventive and unimaginative going forward. His absence badly hurt West Ham, and had he stayed on the pitch, the more likely result may have been a West Ham win.
Instead West Ham suffer a rare home defeat, while Reds fans will be hoping this win can spark a much-needed assault on the table to finally get their season on a more consistent track.