There are two games remaining so the title race is not over yet, but City are firmly in control after a famous success over their local rivals. Thanks for following our coverage of the game and stay logged on for all the reaction.
A huge cheer rings out around the Etihad Stadium as the final whistle goes, with City winning 1-0 to return to the top of the Premier League on goal difference.
The corner comes to nothing but United get the ball back in and Joe Hart is fouled as he jumps for it in the centre.
Patrice Evra gets forward well down the left and wins a corner as his cross is charged down by Pablo Zabaleta.
90+3 Roberto Mancini makes his final change of the night to bring on James Milner for Samir Nasri.
United are desperately trying to get forward and apply pressure on City, but the expected onslaught has not arrived as Gael Clichy slides in to make another important challenge.
The board goes up to signal five minutes of stoppage time, so there is still an opportunity for United to salvage something from this game.
Yaya Toure keeps the ball in down the left, according to the officials, before playing in Samir Nasri in the centre. The Frenchman shows nimble footwork as he is faced with a couple of defenders but cannot quite find the space to get his shot away.
Gael Clichy latches on to a cut-back from Pablo Zabaleta but his shot across goal is kept out by a good diving stop from David de Gea.
Phil Jones is far from happy after conceding a free-kick for a foul on Sergio Aguero, as City remain in control.
Samir Nasri does well to run down the clock for a few seconds by keeping Rio Ferdinand at bay in the corner and then winning a throw-in.
83 United make their third and final change, with Ashley Young replacing the ineffective Nani.
82 Micah Richards is brought on in place of David Silva to further shore things up for Man City in the closing stages.
Yaya Toure comes agonisingly close to doubling City's lead as he curls a shot inches wide of David de Gea's right-hand post, when he could perhaps have played in Sergio Aguero.
79 Michael Carrick fouls Gareth Barry right next to the managers' dugout and is shown a yellow card. Sir Alex Ferguson is not interested in speaking to Roberto Mancini on this occasion.
78 It was something of a surprise that Antonio Valencia did not start but he is on now, replacing surprise Paul Scholes for the closing stages.
Sergio Aguero wriggles away from his defender before attempting shot from a tight angle, which crashes into the side-netting.
76 Nigel de Jong goes in clumsily on Danny Welbeck and is shown a yellow card, but the real action comes on the touchline as Sir Alex Ferguson and Roberto Mancini almost square up to each other, only to be kept apart by officials.
The fans will be getting increasingly tense as we get closer to full-time but United are still struggling to carve out any real openings.
Yaya Toure drives forward with a surging run from midfield before letting fly with a low shot from just outside the area that goes just wide.
70 Phil Jones becomes the first United player to be cautioned following a wild challenge on Gareth Barry in midfield.
Gael Clichy shows remarkable composure to direct the ball back to Joe Hart with his chest even though there are United forwards lurking.
68 Carlos Tevez will not score against his former club tonight as he is replaced by midfield enforcer Nigel de Jong. Quite a surprising decision to withdraw Tevez, but De Jong will add steel to the City midfield.
Carlos Tevez and David Silva show their battling qualities to dispossess Wayne Rooney on the edge of the City area.
United enjoy a brief period of intense pressure before Phil Jones wastes an opportunity to send over a decent cross.
Wayne Rooney throws his arms up in exasperation after failing to find a team-mate with his cross from the left wing, as Gareth Barry heads the ball to safety.
United have still not really threatened Joe Hart's goal but Danny Welbeck has looked lively since coming on, winning a couple of 50-50s.
The impressive Pablo Zabaleta wins another free-kick for City in a dangerous area, which leads to Yaya Toure fizzing in a teasing low cross that causes panic in the United box.
58 Sir Alex Ferguson decides it is time to make his first change and brings on Danny Welbeck for Park Ji-sung to give Wayne Rooney some more support up front.
Pablo Zabaleta gets forward well yet again to help City win a corner. The ball comes back to Samir Nasri but his curling shot from the edge of the area dies not trouble David de Gea.
Chris Smalling fouls Carlos Tevez in the centre of the field and City take the free-kick quickly. Tevez tries to spin away from his marker but Smalling does well to make the tackle.
The game is a bit scrappy just at the moment as both sides try to establish control in the key battleground of central midfield.
53 Yaya Toure is booked for dissent after disagreeing with Andre Marriner's decision to give United a free-kick for a foul on Ryan Giggs.
Pablo Zabaleta shows his underrated attacking prowess to win a corner for City, and Joleon Lescott very nearly gets on the end of it after finding room in the six-yard box.
Joe Hart has not been at his most convincing tonight, as he spills a quick-fire Nani shot from distance to concede yet another corner.
Joe Hart comes out to try and claim the corner but only succeeds in getting his fingertips to the ball and it races away for another corner.
Park Ji-sung links up well with Nani before the Portuguese winger's cross is blocked behind for a corner by Joleon Lescott.
There have been no changes at the break as Sir Alex Ferguson will want the players that he sent out at the start to improve their performance and turn this around.
United get the second half started and they have a deficit to overcome if they are to remain in pole position in the title race.
The half-time whistle goes and City walk off to a standing ovation. They have dominated this match without creating too many chances, but Kompany struck at a crucial time just before the interval and the onus is now on United to respond.
45+1 GOAL David Silva delivers the corner and Vincent Kompany climbs highest to beat Chris Smalling in the air and power a header past David de Gea. The crowd erupts and that goal is fully deserved for City.
Patrice Evra is well positioned to cut out a low cross from David Silva as City continue to build patiently.
Sergio Aguero feels aggrieved as he is muscled off the ball by Rio Ferdinand, but that is strong defending rather than a foul and the referee waves play on.
City are caught napping as the corner is played diagonally to Park Ji-sung just inside the area, but the South Korean blasts his shot way over the crossbar.
While City have definitely been the better team in this half, United still carry an attacking threat on the break and they win a corner here that relieves the pressure.
City break quickly through the centre but Sergio Aguero just cannot find the space to get away his shot and has to settle for a corner, which is well dealt with by United.
City's players just cannot seem to connect properly with their shots at the moment, as Pablo Zabaleta is presented with their latest chance but hits it straight at David de Gea with very little power.
City are certainly knocking on the door here, as Sergio Aguero tries to pick a path through a sea of bodies with a shot that is scuffed wide from inside the area.
Wayne Rooney takes exception to a strong challenge by Carlos Tevez on Phil Jones, and the referee is going to have to work hard to keep emotions in check.
The referee gives a tight decision to United to bring an abrupt end to a promising City attack, and players on both sides are beginning to look a little disgruntled with Andre Marriner.
Park Ji-sung has been working typically hard in the opening stages but he has not played regularly in recent weeks and is dispossessed by Gael Clichy down the United right.
Andre Marriner has a quiet word with Vincent Kompany and Gareth Barry as tensions threaten to boil over, with players on both sides perhaps getting frustrated at a lack of openings.
Yaya Toure tries a shot with the outside of his boot from 20 yards that he makes a complete mess of, but it turns into a decent pass for Samir Nasri as City continue to probe.
Paul Scholes, Michael Carrick and Nani combine well in the United mifield before Gareth Barry slides in on Park Ji-sung with a well-timed challenge.
The City fans are in good voice as the Blues are certainly enjoying the better of things at the moment, although United's defence looks very organised and it may take a moment of inspiration to break the deadlock.
Wayne Rooney's attempted clearance from another corner gets held up in the wind and the ball is played back in to Joleon Lescott, who flicks on to release Sergio Aguero. The Argentine shoots first time with his volley but slices it horribly wide from a tight angle.
City send their big men forward for a corner and Vincent Kompany looks to get on the end of a threatening delivery, but gives away a foul.
City adopt a patient approach with their build-up as they begin to control possession, with United defending quite deep.
19 Referee Andre Marriner plays the advantage following a foul on Wayne Rooney by Vincent Kompany in midfield but Ryan Giggs' cross is intercepted by Joleon Lescott. Marriner returns to the scene of the crime to show Kompany a yellow card.
It is very congested in midfield at the moment as both sides show plenty of energy to close their opponents down quickly when they do not have the ball.
Samir Nasri skips past a couple of challenges before playing in Carlos Tevez, whose dangerous low cross is well cleared by Phil Jones. That is the best moment we have had so far.
Wayne Rooney is fouled by Pablo Zabaleta on the wing and United take the free-kick short, but cannot then find the killer pass and the ball rolls harmlessly out of play.
City are still struggling to find any fluency against a dogged United side and Carlos Tevez and Sergio Aguero have received no service as yet.
Nani tries his luck with a shot from distance but blazes it high into the stands, prompting an ironic cheer from the City supporters.
There are appeals for a penalty as United's players claim that Vincent Kompany has handled the ball inside his own area, but replays show that it came off his chest.
United enjoy a period of sustained possession, with Michael Carrick heavily involved, before Patrice Evra sees another cross charged down to win another corner.
City earn their first corner of the night but it comes to nothing. There is a fantastic atmosphere inside the ground as the Etihad Stadium faithful try to spur their team on to glory.
The early signs are that this will be an open game, as Gael Clichy sprints down the left wing for City before United launch a swift counter-attack.
Phil Jones gets forward well down the right and sends over a looping cross that is safely gathered by Joe Hart, who calls for calm from his team-mates before releasing the ball.
City try to get the ball down and discover a bit of rhythm but United do not want to give them a moment to settle and look much sharper at present.
United win an early corner following good work by Patrice Evra and City look very nervous as Joe Hart struggles to deal with the danger, before it is eventually scrambled clear.
The wait is finally over as Man City kick us off in one of the most eagerly-anticipated games in Premier League history. In a couple of hours' time we will have a much better idea of who will walk off with the title.
A huge roar greets the players as they make their way through the tunnel and on to their field. There is bound to be a lot of anxiety out there, both on the field and in the stands, but this is the type of game that can produce heroes and let us hope it is an absolute thriller.
Sir Alex Ferguson has just been on Sky Sports 1 HD insisting that Manchester United will be going for a win this evening. He has definitely gone with his experienced heads for such a big game and it will be fascinating to see how positively both teams play.
Manchester City are at 11/10 with Sky Bet and Manchester United are 12/5, with a draw 5/2. You can get odds of 11/1 that David Silva will be the first goalscorer, while Wayne Rooney is at 6/1.
There are 20 minutes to go until kick-off but keep those views coming in. Join my colleague Pete Fraser for a live chat that will run throughout the game by clicking here.
"Hey, I'm Ayus Praharaj from Bhubaneswar, India. I'm going for a convincing 1-3 win for Manchester United with Rooney scoring a brace, and Nani also getting on the scoresheet! Go Uniteeedddddd!!!"
Angus in Edinburgh, aged nine, writes: "Well its gonna be a late night but good action. I'm in my City pjs so I think it will have 3 reds and 5 yellows. Wazza with a hat-trick and Tevy with 2 and that to be the final score. Come on the City."
"Hi it's Josh, I am a united fan and i think that people have got to be realistic in what they say. I believe it will be a very different defensive performance by both teams and one goal will decide it. I think that with United's current run of high goalscoring matches that United will barely come on top early in the second half with Paul Scholes to score from range. 1-0 to United."
Scot in Ft Lauderdale: "Sir Alex has certainly loaded his team with experience. The only familiar name missing from this line up is Captain Mainwaring!"
"Hi, David a Walsall fan from Walsall. Would love to see Manchester City to win tonight and throw the title chase straight to the wire, would love a new name on the trophy, always liked City ever since they were promoted with The Saddlers back in 1998/99 - Weird to see them challenging for the title while Walsall are battling against relegation to League 2. I predict 1-0 to City with a Carlos Tevez winner in the last 5 minutes."
Chris Dunkerley says: "That United team is a disgrace. How can they possibly compete. They do not deserve to win this match let alone the league. City to win 3-1."
Jim in Taiwan says: "Late night but hope it's going to be worth it.I'm a Leeds fan so obviously hoping for a City win. I predict 4 red cards..loads of gum chewing."
Manchester City are unchanged from the team that beat Wolves 2-0 last time out, meaning that Carlos Tevez will line up against his former club as he continues his strike partnership with fellow Argentine Sergio Aguero. Sir Alex Ferguson has decided to make four changes, bringing in Ryan Giggs, Phil Jones, Chris Smalling and Park Ji-sung.
Man Utd: De Gea, Jones, Smalling, Ferdinand, Evra, Nani, Carrick, Scholes, Giggs, Park, Rooney. Subs: Amos, Berbatov, Hernandez, Young, Welbeck, Rafael, Valencia.
Man City: Hart, Zabaleta, Kompany, Lescott, Clichy, Silva, Y Toure, Barry, Nasri, Tevez, Aguero. Subs: Pantilimon, Richards, Milner, Dzeko, Kolarov, De Jong, Balotelli.
Harry says: "So excited yet anxious about this game can't wait for kick-off. As a United fan I want United to win I think the final score will be 4-1 to United! Come on you Reds title N0.20 is on the way!"
Qasid in Bromley writes: "I'm a Man Utd fan and I know that this will be an incredibly close match with both teams trying to go for the win. Aguero and Tevez to score in the first half before Utd produce a fight-back with Rooney to score before 60 mins and let's say Hernandez to level the scoreline in stoppage time. Oh and De Gea to make a penalty save somewhere along the way."
"Hi, I'm Harry from Newbury, this is going to be one hell of a game, I think Fergie has the edge here, but this all depends on his selection, Man city have been riding their luck all season and certainly have a fear factor against most clubs in the Premiership, but these kind of games really do suit Utd and they will overcome I'm sure, City still need a point to prove and both sides have a defence that is leakable, with goalscorers wanting to stamp their mark, so goals to be had tonight so I'm going with 3-2 maybe 4-2 utd, there will be goals there usually is......."
John Bagust in Prague says: "United will not lose tonight.They have the experience to handle City at this moment in the title race. 0-1 to Utd with a goal from Rooney. Shame tomorrow is a day off here in Prague - would love to see some of my City colleagues after we win!"
These two sides have played out some thrilling matches over the past few seasons and have already met this season in a couple of memorable encounters. City stunned United with a 6-1 victory at Old Trafford that really underlined their title credentials, but the Red Devils did gain some revenge with a 3-2 win at the Etihad Stadium in the FA Cup.
Arthur Albiston writes: "I feel Sir Alex has a lot more options than Mancini - you could probably pick most of the City lineup but Fergie will keep you guessing. I would be happy with a point but have a feeling United will break City hearts (or Hart) with a late winner - 2-1 United."
Spurs fan Stu says: "Evening Lewis, hoping for an exciting game for the neutral tonight..! I'm going for 3-2 to Utd, Rooney to get at least 2. And 3-2 at 28/1 not a bad shout"
Gabriel Sutton is the first to get in touch, saying: "Dead excited about tonight's game, even as a neutral Birmingham city fan! Gutted I'm out playing table tennis tonight but hopefully I can catch the highlights later on. Whilst I can't wait for the game, I think the winner will definitely win the title, there could be an element of nerves and anti-climax about it. I could see a 0-0 draw." Tough choice Gabriel, a night of table tennis or the Manchester derby.
The two managers have taken very different approaches in the build-up to this match, without really entering into the traditional 'mind games'. Sir Alex Ferguson has described it as the 'derby of all derbies' and the biggest he has been involved in since becoming United manager, while Roberto Mancini has tried to play down the hype by insisting his players are still not under pressure. Mancini believes United will remain title favourites even if City win today, as their final two games are 'easier'. For the record, City go on to play Newcastle and QPR after this match, while United will face Swansea and Sunderland.
Right, let's start with a reminder of exactly what the situation is at the top of the table. Manchester United have a three-point lead over their local rivals and a victory this evening would leave them on the brink of winning the title with just two games remaining this season. A draw would keep the Red Devils in pole position but ensure a fascinating final fortnight, while City will go top if they win tonight as they have a superior goal difference. Roberto Mancini's men are unbeaten at home in the Premier League this term and go into this game in better form than United, having been eight points adrift just a couple of weeks ago.
There may still be an hour and 40 minutes until kick-off at the Etihad Stadium but please get in touch with your views and predictions. We have a live chat already up and running with my colleague Pete Fraser so please join in here. There is plenty to talk about so keep those opinions coming all evening. You can also get in touch with me before the game at Lewis.Rutledge@bskyb.com or via Twitter @SkySportsLewis, and why not check out our wide array of pre-match features, including an opportunity to pick your combined XI from the two clubs.
Welcome to our minute-by-minute commentary of Manchester City's clash against Manchester United. Excitement has been building for the past few weeks and unless you have been living in a cave you will be aware of what is at stake in perhaps the biggest Premier League match in history. One of these teams will be crowned champions within the next fortnight and it will be all the more special for those supporters toasting success because the other half of Manchester will be drowning their sorrows. So for tonight forget about everything else and just enjoy the game. It really is unmissable.