After nine years without a trophy Arsène Wenger now has two in two games as a breezy performance marked by three excellent goals secured a Community Shield victory against a weakened Manchester City. It is the first time Arsenal have won the shield in a decade and comes three months after their last official match resulted in victory on the same pitch in the FA Cup final against Hull City.

Quite what it means remains to be seen. City looked like a team still in hibernation while Arsenal, as they must with Champions League qualifiers against Besiktas coming up, seemed a step more advanced in their preparations.

Indeed, if confirmation were needed that this is little more than a semi-contest for a semi-trophy that fades from the memory come the first whistle of the season proper, then it is worth sparing a thought for last season’s winners. Twelve months ago victory in the Community Shield was hailed as the first step in the David Moyes Revolution at Manchester United (also, as it turned out, the only step).

This is not to belittle Arsenal’s achievement in beating the champions convincingly with a fine attacking performance that provided above all a reminder of the qualities of Aaron Ramsey, Santi Cazorla and Jack Wilshere, who looked fit and mobile and passed the ball well in central midfield.

This was an engaging, agreeably carefree kind of match from the start on an August afternoon that kicked off with the sun breaking through after a thunderstorm and the Wembley turf emitting a kind of luminous green steam. Wenger’s lineup contained all three significant outfield summer signings – Mathieu Debuchy, Calum Chambers and Alexis Sánchez – while City included both Fernando, the £12m summer signing from Porto, and Willy Caballero in goal.

In the opening minutes Sánchez combined nicely with both Yaya Sanogo and Ramsey, who showed a willingness to run in behind Gaël Clichy at right-back as Arsenal set about trying to make their extra man count in midfield. City lined up here in the now fashionable 4-4-2, with Edin Dzeko and Stevan Jovetic playing as a pair of genuine centre-forwards, albeit without the same tenacious commitment to tracking back that made the system work for Atlético Madrid last season.

Most of Arsenal’s early pressure came down the right side, with Sánchez taking the chance to run at Aleksandar Kolarov and Debuchy eager in support. Chambers also looked composed in central defence: one early challenge on Yaya Touré, easing off the ball a man who generally yields only to some form of hydraulic-lifting equipment, will have given him great heart.

For all that, neither team had managed a shot on target before Arsenal opened the scoring in the 21st minute via a combination of slick play by Cazorla and some loose City defending. There seemed no obvious chance of a goal when Cazorla picked up the ball from Sanogo 30 yards out but Dedryck Boyata’s mistimed lunge allowed the Spaniard to roll the challenge and find some space on his left foot. Clichy could not get there in time and Cazorla shot low across Caballero and into the far corner.

Cazorla had rescued Arsenal’s Cup final in May and here he sparkled again, producing a reverse pass inside Clichy to set Sanogo in on goal. Sadly the finish from the Frenchman belonged to an entirely separate footballing universe, another scuff from what seems to be an inexhaustible reserve of shins, pokes, flails and mis-hits.

Sanogo is hugely willing and will improve, but he is still learning how to play at this level in a team that are undeniably short in his position.

Seven minutes before half-time there were huge cheers around Wembley when the referee Michael Oliver used his vanishing spray for the first time, producing a neat, hand-drawn circle – mark of the true artist – around the ball, only for Touré’s execution to fall some way short of his art work. And just before the break Arsenal doubled their lead with a goal of real craft on the counter-attack. Sánchez carried the ball forward and fed Sanogo who produced exactly the right pass inside to Ramsey at exactly the right moment. From there two expert touches made the goal: a jink inside Matija Nastasic and a low, hard shot into the corner.

At half-time an occasion that so often feels as though it never really got going felt as though it was all but over, with City not so much uninterested as undermanned and undercooked. Indeed, the champions looked like what they were: a team with nine first-team players missing including the captain, main goalscorer and chief creator in David Silva.

Silva did come on at the start of the second half and City were briefly energised, Jesús Navas taking a fine long pass from Touré and crossing deep for Jovetic to head the ball down. Wojciech Szczesny palmed the bouncing ball away at his near post. It proved something of a false dawn as Oliver Giroud made the score 3-0 after 60 minutes. What a goal it was, too. Taking a pass from Wilshere, the Frenchman, who had looked barely fit in his previous appearances, carried the ball forward and hit a dipping shot that deflected over Caballero from 20 yards.

For all the mildness of the occasion Arsenal will take great heart from victory here, not least from the performances of Ramsey and Cazorla and a hugely promising debut from Chambers, who looked a genuine presence at this level.

Far sterner tests await, though, than this weakened City, who had 58% possession and more shots on goal overall but still looked like a team simply stretching their legs.