With the Gunners in control of the tie following their fine 3-0 victory in Zagreb, tonight was always set to be something of an anti-climax at the impressive Emirates Stadium.

Despite the magnitude of their task, the visitors started brightly and it was no surprise when they took the lead through Eduardo.

It was at least a more composed display from Wenger’s side in the second half, when Thierry Henry came of the bench for the final 20 minutes.

Freddie Ljungberg’s deft header looked to ensured a face-saving draw on the first European night at Arsenal’s new home – with Mathieu Flamini winning the match with a close-range finish in stoppage time.

However, with the likes of AC Milan, Barcelona, Real Madrid as well as, of course, Chelsea, Manchester United and Liverpool all out to mount a sustained challenge over the latter stages of this elite club competition, Wenger will be all too aware of the necessity to find their form when it matters when the Champions League resumes next month.

The Gunners had tonight seemed content to sit back and soak up plenty of early pressure, which did not really go anywhere.

But the home side were eventually undone after 11 minutes, when Eduardo played in Etto down the left, who cut a pass back into the area.

Kolo Toure made a complete hash of his attempted sliding interception.

Eduardo has continued his run – and was on hand to slot the loose ball under Almunia, into the bottom left corner.

Wenger looked less than best pleased as the travelling ranks of Zagreb fans celebrated, drums and all – with many of the hardened ‘Bad Blue Boys’ from eastern Europe electing to remove their shirts on what was a mild evening in north London.

Arsenal then immediately raised the tempo.

Agic was booked for a late challenge on Robin van Persie, with the resulting free-kick deflected behind.

On 25 minutes, the Gunners should have been level. A free-kick into the box was headed down by Emmanuel Adebayor and the loose ball dropped to van Persie, who drove a low shot goalwards from six yards.

Somehow, though, Mario Cvitanovic made a block, the ball cannoning up onto the crossbar and bouncing just the right side of the line.

Keeper Ivan Turina then made a smart save at his near post to deny the lively Dutchman.

Ljungberg – Gunners captain for the night – was the next man to wasted a golden opportunity, stabbing the ball straight at Turina when it fell kindly for him at the far post.

There was another warning for Arsenal on the half-hour when Luka Modric flashed a low, angled shot just wide from 18 yards.

Then, in stoppage time, Etto weaved his way into the Arsenal box down the left and drilled the ball just wide.

Arsenal should have levelled eight minutes into the second half.

The ball was whipped across the Zagreb box from the left, with a deflection taking it right into the path of Adebayor.

The Togo striker – no more than 10 yards out – had all the time in the world, but somehow managed to blaze his rushed effort horribly high into the stands.

Arsenal were stepping up the pressure, however again the home side lacked the final ball to unlock the Zagreb defence.

With 26 minutes to go, Wenger turned to his talisman.

The Emirates Stadium duly applauded the arrival of Henry, so often the Gunners saviour, with Adebayor the man to make way.

Henry’s first job was to take a free-kick in the left side of the penalty area, which he floated towards the back post and had Turina scrambling to fist clear.

Johan Djourou was somewhat fortunate to only be shown a yellow card for a late, high challenge on Etto as the Zagreb striker looked to skip clear.

Eduardo whipped the resulting 20-yard free-kick just wide.

Arsenal were finally level with 13 minutes left when Ljungberg glanced in van Persie’s cross from the right.

There was still time for another cameo from England youngster Theo Walcott, replacing van Persie for the closing stages.

In stoppage time, Flamini won it when he stabbed in from close range following the teenager’s low centre.

By then, though, tonight’s work had been done, and the Gunners can look forward to tomorrow’s draw in Switzerland. Plenty of hard graft, however, is very much still to come.