Nani's double gives neighbours – and the rest – a rousing reminder

Five goals, one shield and no sense of community. If Manchester's two clubs gave us a taster yesterday of the Premier League season that awaits us on Saturday, then roll on the weekend. Just think what it will be like when it really matters.

In the closing minutes of yesterday's game, just before Luis Nani seized on a mistake from Vincent Kompany to run in United's winner, there was a greater sense of tension than at the same stage of United's last game in this stadium 72 days earlier. Then, they were helpless as Barcelona saw out the Champions League final; yesterday, at least they had something to play for and threw everything at it in the second half.

Two goals down after a first half that they had the better of in terms of possession, United came roaring back with a team that was very young; indeed, Ashley Young, at 26, was the oldest player on the pitch until Dimitar Berbatov came on for the last few minutes. Roberto Mancini complained that his team lost "control" of the game but it would be a stretch to say they ever had it.

What City did have were two sweetly taken goals in the first half, the first a glancing header from Joleon Lescott from a free-kick from the right. The second was a shot thumped at goal by Edin Dzeko from a good 35 yards out which seemed to mesmerise David de Gea, who failed to get his hands and feet in order quickly enough to get down to it and push it away.

The sight of the new United goalkeeper trudging off forlornly at half-time, probably wondering if he might have done better with both City goals, threatened to be the defining theme. De Gea has one of the most daunting tasks in football, taking the place of Edwin van der Sar at a club that had proved a graveyard for the reputations of some very decent goalkeepers.

It did not work out like that. De Gea redeemed himself with a couple of good saves in the second half, the first from Adam Johnson and then from Micah Richards who, it turned out, had fouled Chris Smalling as he powered in a header from close range. These are early days yet for De Gea but, as he looked around the stadium yesterday at 77,169 fans screaming for victory in an early-August friendly, he will have concluded that those who told him English football was intense were not lying.

In the end, it was United's young team who carried the day, notably with a wonderful, seven-pass second goal. Sir Alex Ferguson finished with a back four, from right to left, of Smalling, Phil Jones, Jonny Evans and Rafael Da Silva and an average age of 21. Jones, who has added a dash of peroxide to his hair to mark his transition into the Premier League big time, looked very comfortable as a second-half substitute.

Even with Berbatov on at the end of the game, the average age of United's entire team was 23. In midfield, Tom Cleverley, 21, who came on at half-time, looked sharp. United teams do not change overnight but yesterday you could see the reasoning behind Ferguson's acquisitions policy over the last two years and his plan for the future.

It probably did not require the post-match needle from Wayne Rooney, who tweeted that City had been given a "footballing lesson" by their neighbours, but we got it nonetheless. Unless you had not already noticed, Manchester football is somewhat tense at the moment, as Rooney must have been aware when he made his incendiary comment.

There were seven bookings in the game, including one for a studs-up lunge by Richards on Young that might have prompted greater punishment in a Premier League game. City looked like they were struggling to get a foothold in the match until Lescott got between Nemanja Vidic and Rio Ferdinand to get his head on David Silva's cross from the right and glance it past De Gea.

There was a suspicion that Lescott had a handful of Ferdinand's shirt as the ball came in but, nonetheless, for such an experienced defensive pairing, it was an error to leave their young goalkeeper so exposed. City came to life, Yaya Touré's ball down the inside-right channel to James Milner won a free-kick when Evra fell on top of the player. Then, in added time at the end of the first half, Dzeko beat De Gea again.

The now well-worn statistic that De Gea was beaten 11 times from outside the area for Atletico Madrid last season, the highest of any goalkeeper in La Liga, might be a clue to a weakness in his game. Having said that, he is only 20 years old. Still, there is no hiding place for a United goalkeeper.

The three substitutes Ferguson brought on at half-time – Evans, Cleverley and Jones – looked at first glance like a ruse to downgrade the game's importance. In fact, the opposite was the case. United achieved a fluency in midfield that even Silva could not match and Young gave them impetus. Dzeko was supposed to be marking Smalling when, on 52 minutes, the United defender crept in behind City's back four and guided Young's free-kick past Joe Hart.

The equaliser five minutes later was a beauty. There were seven passes by United to work their way around and through City's defence, involving Rooney, Cleverley, Welbeck and Nani before the ball was returned to Nani, who accelerated past Hart and scored from close range.

It would have been intriguing to see Sergio Aguero called from the bench at that point but Mancini is Mancini – he rarely does the most obvious thing. He replaced the largely ineffective Mario Balotelli with Gareth Barry and the Italian disappeared straight down the tunnel. He gave Johnson the last 23 minutes, but of the Argentine there was no sign.

Kompany's fatal hesitation in dealing with Rooney's long clearance in the 94th minute game let Nani steal the ball and run at goal and his finish was very smooth. Having lost last season's FA Cup semi-final to City at Wembley, United celebrated this win with an unexpected fervour. But then there is a new team emerging here – and for at least four of them it counts as their first trophy.

Match Facts

Substitutes: Manchester City Barry, (Balotelli, 59), Johnson (Milner, 67), Clichy (Kolarov, 73). Manchester United Jones (Ferdinand, h-t), Cleverley (Carrick, h-t), Evans (Vidic, h-t), Rafael (Evra, 71), Berbatov (Welbeck, 89).

Booked: Man City Dzeko, Richards, Y Toure, Milner, Kolarov. Man United Anderson, Evra.

Man of the match: Nani. Match rating 9/10.

Possession: Man City 44% Man United 56%.

Shots on target: Man City 6 Man United 12.

Referee: P Dowd (Staffordshire) Att 77,169.