AFP IS CLOSING THIS LIVE REPORT after Manchester City claimed a morale-boosting 2-1 victory over their city rivals and Premier league leaders Manchester United thanks to Sergio Aguero's winner 11 minutes from time at Old Trafford.
Manchester City striker Sergio Aguero (R) celebrates in front of the United fans after scoring their second goal during the Premier League match at Old Trafford in Manchester, northwest England on April 8, 2013. City won the game 2-1.
The derby victory went some way to restoring pride for City but still leaves Alex Ferguson's side 12 points clear with seven games to go and hot favourites for the title that City claimed last year.
James Milner had put the visitors ahead with a deflected right-footed effort on 51 minutes before Phil Jones's header went in off City captain Vincent Kompany to level it for the hosts eight minutes later.
But City boss Roberto Mancini sent on Aguero for Samir Nasri with 20 minutes left and the Argentine striker repaid his manager's faith with a scintillating individual goal which saw him escape Danny Welbeck and Phil Jones in the United area before firing home the winner.
Read on to find out how City won Manchester bragging rights and ended United's 18-game unbeaten streak in the league, gaining some revenge for United's 3-2 win at the Etihad in December:
2128 GMT: United boss Alex Ferguson questions whether the opening goal from James Milner should have stood, arguing that Carlos Tevez was offside when the midfielder fired in his shot and interfering with play as he was in David De Gea's eyeline.
"Tevez was interfering with play for the first goal -- if that's not interference I don't know what is," Ferguson tells Sky Sports television.
"It was a very intense game between the two best teams in the country.
"But it's not a bad day in terms of performance -- you don't want to lose a derby game but we're ok.
"We've got a 12-point lead and there are seven-games to go."
2120 GMT "We are happy - we played football and we deserved to win," City boss Roberto Mancini tells Sky Sports television.
"We played football, we played very well and we deserved to win.
"We had the ball, we kept the ball and we showed that we didn't deserve to be 15 points behind."
But asked about any lingering title aspirations, Mancini is unmoved from his pre-game pessimism.
"It's finished," Mancini says. "But it's important that we finish in second position."
On the reason for United's lead in the league, Mancini says the key has been United's goal-scoring prowess.
"We are like them - but they have scored more than us and that is the difference."
2108 GMT: James Milner is delighted with his side's derby victory despite it doing little to boost City's hopes of fighting back in the title race.
"It's always tough coming here and getting a win but we managed to do that," Milner tells Sky Sports television.
"A derby's a derby - it was massively important, we came here and worked hard."
His captain Vincent Kompany seems to have already come to terms with City's loss of the Premier League title to, switching the focus to the 2013-14 season.
"I do believe the way we finish this season will have an impact on next season," he says.
90+5 mins: FULL-TIME - Manchester United 1 Manchester City 2
City have ended United's 18-game unbeaten run in the league -- and restored some pride -- but their title remains likely to head to Old Trafford with the gap between the sides still at 12 points.
90+3 mins: YELLOW CARD! The late flurry of cards continues as United's Rafael is booked for catching Sergio Aguero who was breaking forward at pace.
SUBSTITUTION: Javi Garcia has replaced Carlos Tevez.
90+1 mins: YELLOW CARD! Pablo Zabaleta follows his teammate into the book for a rash challenge from behind on Ashley Young.
90 mins: YELLOW CARD! City's Gareth Barry into the book.
There will be four minutes of added time - can United find a leveller?
87 mins: CHANCE! Robin van Persie whips a corner in from the right towards Phil Jones at the back post but Ivorian midfielder Yaya Toure puts the defender under enough pressure to force the him to send his header wide.
85 mins: SUBSTITUTION: United make a change, sending Javier Hernandez on for the largely ineffectual Wayne Rooney -- last throw of the dice for Ferguson?
84 mins: CHANCE! Rafael whips the ball in from the right and onto the head of Robin van Persie but the Dutch striker's header is straight at Joe Hart.
80 mins: SUBSTITUTION: Antonio Valencia replaces Danny Welbeck for United
79 mins: GOAL! Manchester United 1 Manchester City 2
Sergio Aguero has reclaimed the lead for City - the Argentine striker drives into the area, escaping from Danny Welbeck and Phil Jones before firing a right-footed shot past a despairing David De Gea.
That was Aguero's 10th league goal of the season and may have earned City a morale-boosting win here.
77 mins: Danny Welbeck has been marauding down both flanks and posing a real threat for United -- he gets th ball on the left of the area before pulling it back to Ashley Young who fires in a crisp right-footed shot but straight at Joe Hart.
73 mins: Gareth Barry has taken a knock on the head near the centre circle and is grimacing -- the City midfielder went up for a header with Robin Van Persie but it was his teammate Matija Nastacic that seemed catch him.
71 mins: SUBSTITUTION: Mancini makes a change for City -- Argentine striker Sergio Aguero come on to replace French midfielder Samir Nasri.
59 mins: GOAL! Manchester United 1 Manchester City 1
Yaya Toure concedes a soft free-kick on the right with a foul on Rafael -- Robin van Persie steps up to whip a vicious right-footed free-kick into the six-yard box.
Phil Jones fires in a header and wheels away in celebration but replays show the ball had been heading wide and before striking Vincent Company on the back before going over the line.
51 mins: GOAL! Manchester United 0 Manchester City 1
James Milner gives City the lead with a left-footed strike from the edge of the area that deflects past David De Gea.
Ryan Giggs gave the ball away in the build-up -- that was only Milner's fourth league goal of the season.
2002 GMT: City get the game restarted at Old Trafford.
1955 GMT: United fans were poking fun at their City rivals with this pithy chant in the first half:
"Keep singing 6-1, keep singing 6-1, six games in Europe, you didn't win one" (a reference to City's famous 6-1 win at Old Trafford, which admittedly was 18 months ago now...)
Touche.
45+1 mins: HALF-TIME - Manchester United 0 - Manchester City 0
Mike Dean blows the whistle for the interval just as a Gael Clichy cross flies into the United box from the left after a concerted period of pressure -- City's players aren't happy, surrounding Dean and demanding an explanation but he just points at his watch.
42 mins: YELLOW CARD! Vincent Kompany into the book for an uncontrolled lunge towards Young who has to leap out of the way. Seems a justified booking as that was rash.
38 mins: CHANCE! Wayne Rooney breaks down the middle before finding Ashley Young to his left. Young jinks past Pablo Zabaleta before moving the ball onto his left foot and firing in a cross-shot but it's well-blocked.
35 mins: James Milner whips a dangerous free-kick into the United area from the left flank - but a United defender heads it to safety. City getting some joy down the left.
29 mins: YELLOW CARD! David Silva in the book for a deliberate handball. Pablo Zabaleta whips the ball in from the right and TV replays show the Spaniard stuck an arm up to get to it ahead of Rio Ferdinand so that caution seems justified.
TV pictures show Mancini laughing, presumably at that decision by referee Mike Dean, but if he sees the replays he can have few complaints.
26 mins: CHANCE! Good opening for City - David Silva plays the ball towards the area and it bounces off Ryan Giggs to the feet of Samir Nasri but the Frenchman slices a right-footed shot wastefully wide of De Gea's goal.
20 mins: "Mancini out in his technical area bellowing orders following Van Persie's chance for United," writes Chris McKenna, at Old Trafford covering the game for AFP.
17 mins: Good play from Gareth Barry on the left, jinking past two United players before whipping in a cross which Milner heads down to the feet of Carlos Tevez. The Argentine striker controls it but Rio Ferdinand nicks it off his toes for a corner.
12 mins: It's fast and furious at the start here, both teams passing the ball at a frightening pace - City try to work an opening on the edge of the City area with Samir Nasri finding David Silva but United's defender snuff it out.
9 mins: CHANCE! First threat from the hosts - Wayne Rooney shrugs off Matija Nastacic and chests the ball down before turning to find Robin van Persie in the box - the Dutch striker works it onto his left foot and fires in a rasping low shot but wide of Joe Hart's left-hand post.
3 mins: First opening for City who have burst out of the blocks - James Milner gets to the righthand byline and whips a low right-footed cross across the six-yard box aimed towards Carlos Tevez but United 'keeper David De Gea palms it to safety.
1900 GMT: KICK-OFF - The game's under way in front of a full house at Old Trafford.
1858 GMT: United fans ans at Old Trafford chanting "Campeones, Campeones" as both sets of plays walk out onto the pitch.
"Interesting battle is Giggs and Carrick v Toure and Barry. Could be the difference," writes Chris McKenna, at Old Trafford covering tonight's game for AFP, via his Twitter account @cmckennasport.
1855 GMT: Five minutes to kick-off - can City become just the second club to take any points from Old Trafford this season? The only blemish on the hosts' otherwise perfect home record is a 3-2 defeat to Tottenham in September.
1850 GMT: City have made two changes from their last game, a 4-0 home win over Newcastle -- centre-half Joleon Lescott and striker Edin Dzeko dropped to the substitutes' bench, along with Argentine striker Sergio Aguero.
1845 GMT: Here are the full teams:
Man Utd: De Gea, Da Silva, Ferdinand, Jones, Evra, Young, Carrick, Giggs, Welbeck, Rooney, van Persie. Subs: Lindegaard, Valencia, Hernandez, Nani, Cleverley, Kagawa, Buttner.
Man City: Hart, Zabaleta, Nastasic, Kompany, Clichy, Barry, Toure, Milner, Nasri, Silva, Tevez. Subs: Pantilimon, Lescott, Dzeko, Kolarov, Javi Garcia, Aguero, Toure.
Referee: Mike Dean (Wirral)
1840 GMT: Alex Ferguson has been talking to Sky Sports television before the game - he sounds philosophical about having to replace Phil Jones at centre-back in place of the injured Nemanja Vidic:
"We have three centre-backs out but that's been the story for a while -- we have to get on with it," says Ferguson.
"Phil Jones hasn't played at the back much but he is an outstanding footballer, he'll be fine. It's a game we want to win.
"There are a lot of good footballers out there tonight, both teams want to keep possession and get settled. It wouldn't matter if we were at the bottom of the league, the intensity of a derby game makes it special."
1835 GMT: Team news for United -- Wayne Rooney is back in the side after a two-game absence with a groin injury while Robin van Persie also returns after being rested in United's FA Cup quarter-final defeat at Stamford Bridge last Monday.
Centre-back Nemanja Vidic is still missing with a back injury.
1825 GMT: City boss Roberto Mancini talking to Sky Sports television and is asked how he feels about trailing United by a 15-point margin -- the Italian is more magnanimous than in his pre-match press conference:
"It's difficult -- we can't win the title for this reason," Mancini says. "We should have respect for the other team they did better than us, that's the reality."
1812 GMT: "Half and half scarves, title not really on the line, tame Manchester derby or will the battle on the pitch say differently?" writes Chris McKenna, at Old Trafford covering tonight's game for AFP, via his Twitter account @cmckennasport.
WELCOME TO AFP'S LIVE REPORT on the top-of-the-table derby between Premier League leaders Manchester United and second-placed Manchester City at Old Trafford.
With United 15 points clear of their city rivals with just eight games to play, Roberto Mancini has been forced to concede his side's reign as champions is all but over.
But City supporters won't let United fans forget their 6-1 humbling in this fixture last season and another win on enemy territory would partially ease the pain of surrendering the title and prove they can hold their own against Alex Ferguson's champions-elect.
If City manage to beat United they will join the select band of only three clubs to have beaten them in the league this season -- Everton, Tottenham Hotspur and Norwich City -- but with United having won their last seven straight league games City have their work cut out.
The reverse fixture at the Etihad in December was decided by an injury-time free kick from Robin van Persie as United won 3-2.
Kick-off is in an hour away at 2000 BST (1900 GMT) -- stay with us for all the action as it unfolds.