Whether Vieira’s absence from the side is more long-term than his current thigh injury remains to be seen as Real Madrid and Arsenal continue their summer battle of wills over his future.

But in an entertaining encounter, Vieira’s normal midfield partner, Gilberto, put Arsenal ahead before Alan Smith, in an impressive all-round display, soon levelled with a thunderous shot.

Arsenal were nevertheless unbowed and Reyes, who earlier squandered a golden chance, made amends amid some worryingly hesitant United defending ahead of their Champions League qualifier next week.

Indeed, the Spanish international, who has grown in stature and physique since his first few months in English football, just proved what an impact he is set to make on the Barclays Premiership this season.

However, so haphazard was United’s defending in the final stages that Mikael Silvestre’s own goal gave Arsenal’s victory a touch of polish and will have set Alex Ferguson’s alarm bells ringing.

For while the Community Shield matters little to him, the Champions League qualifying round against Dinamo Bucharest, which starts next week, is of paramount importance.

And with a host of key players still missing, he has tough selection problems ahead of him, even if Arsenal were also without several first-choice figures in Cardiff.

At least they had Thierry Henry available again after injury and, especially with him and Reyes in full-flight, they were simply far sharper and quicker than their opponents.

The Gunners’ finishing was initially awry, with Bergkamp lobbing one effort just over the bar and then seeing a drive held by Tim Howard.

Henry, meanwhile, responded to a cigarette lighter being thrown close to him with a free-kick that was just tipped over.

Bergkamp also fell over his own feet when clean through, while Jermaine Pennant lazily miskicked the ball wide after Howard could only parry Henry’s shot.

Pennant, back after a loan spell at Leeds, was nevertheless one of the more penetrating figures on display, even if it was a former Elland Road team-mate who sprang to life just before the break.

Smith, who tirelessly led the line on his own in Ruud van Nistelrooy’s absence, blazed one effort wildly over the top, but had another shot well saved by Jens Lehmann.

The Arsenal goalkeeper was further called upon to deny Paul Scholes, while he also tipped over a diving header from Gary Neville after the full-back had been picked out by Smith.

The half-time interval nevertheless handed the initiative back to Arsenal and, even after replacing Henry with Robin van Persie, they finally found their finishing touch.

Reyes moved up front full-time and soon glided effortlessly past first Silvestre and then Howard only to somehow contrive to hit the sidenetting when the goal was seemingly at his mercy.

But while Reyes held his head in his hands, he was handed a reprieve within 60 seconds as United, who had tried to reorganise their defence, squandered possession and allowed Arsenal to break again.

This time, when Reyes burst clear and approached Howard, he sensibly squared a pass straight into the path of Gilberto, who had arrived ahead of van Persie to guide the ball home.

That prompted three United changes, with Roy Keane, Ryan Giggs and Quinton Fortune all taken off to save their legs ahead of next Wednesday’s Champions League qualifier.

And although Arsenal almost went further ahead, when van Persie headed Bergkamp’s cross just past the post, United were, in fact, quickly level.

Smith charged down an attempted clearance and although the linesman started to raise his flag as Diego Forlan was offside, he was deemed not to be interfering with play as Smith thumped the ball into the net from 25 yards out.

Then again, the lead promptly changed hands almost as quickly as Sven-Goran Eriksson seems to change partners as Arsenal struck back almost immediately.

The United defence were unable to deal with Bergkamp’s cross as it bounced off Gilberto and Reyes was given far too much time in which to swivel and fire his shot past Howard.

As United’s defending in the continued absence of Rio Ferdinand became almost comical at times, teenager Cesc Fabregas – Vieira’s effective midfield replacement in Cardiff – shot just wide.

And when Cole burst through several weak challenges, his attempted cross cannoned off Silvestre’s leg and trickled past the stranded figure of Howard as United’s embarrassment was complete.

Indeed, even with the Vieira saga continuing in north London, it is Ferguson who enters next week with rather more pressing concerns on his mind.