When their Champions League supposed 'moment of truth' came, Arsenal were still found wanting as they failed to overcome even a Roma side reduced to 10 men for almost 70 minutes at Highbury.

However, despite the deep frustration levels at the Gunners' failure to win at home in Europe for the fifth time this season, Arsene Wenger's side still have a second chance to redeem themselves.

That it will come next week in Valencia's imposing Mestalla Stadium is, some would say, scant consolation for the way in which the Gunners surrendered an early lead secured by Patrick Vieira.

Even after Roma's normally inspirational captain, Francesco Totti, was controversially sent off for a confrontation with Martin Keown, the Italian side still managed to equalise on the stroke of half-time through Antonio Cassano.

And despite Arsenal's plethora of missed chances, it was actually Roma substitute Vincenzo Montella who squandered the clearest opening of all as he headed over the top from six yards out in the final stages.

So however confident Wenger may have been before kick-off, speaking in terms of a 'moment of truth' for his side to prove their European credentials, the jury is still out on Arsenal's ability to transform their superb Premiership form into the Champions League.

It was in Valencia that they were eliminated at the quarter-final stage two seasons ago, being unable to secure the draw they needed to make it through.

Whether they have grown in stature or experience since then will be tested to the full next week in Spain after Valencia secured a draw against Ajax to leave the group tantalisingly up for grabs.

Calculators are therefore needed, although it could all have been so much simpler if Arsenal had managed to capitalise on their storming start at Highbury.

After all, with just 12 minutes gone, Vieira rose unchallenged to flick Giovanni van Bronckhorst's corner past keeper Ivan Pelizzoli.

The Arsenal skipper almost struck again soon afterwards, this time with a diving header from Robert Pires' cross, and the Gunners were comfortably in command.

Indeed, Roma's task was then magnified considerably when Totti, who had already clashed twice with Keown, threw out an arm towards the Arsenal defender's head as they contested the ball.

There was contact but it was minimal and replays proved there was no elbow involved, but referee Urs Meier still showed the Roma captain the red card for what he deemed to be a deliberate act.

The Italian side's frustrations grew thereafter, with Cassano earning a furious reprimand from Francisco Lima for earning a yellow card for dissent.

In a physical encounter, the frequent stoppages interrupted Arsenal's rhythm, but the home side were also guilty of over-elaboration.

Thierry Henry's surging run set up Sylvain Wiltord only for Pelizzoli to deny him at the near post, Pires had a header ruled out for offside and then Dennis Bergkamp flashed a shot across the face of goal.

Arsenal failed to make the most of their domination of possession though and were caught napping at the back just before the break as Pascal Cygan failed to cut out a long through ball by Emerson.

Cassano was left in space to beat the offside trap and he nipped ahead of David Seaman to the ball before rounding the Arsenal keeper and guiding his shot into the unguarded net.

Arsenal's pressure duly resumed after the interval but so too did their profligacy, with not even Henry or Pires immune.

Wiltord was nevertheless the main culprit, being denied by Pelizzoli after being put through by Bergkamp and then blazing another effort over the top.

Roma were content to threaten on the counter-attack, with Keown just managing to hold off Emerson as the Brazilian international attempted to muscle past him into the penalty area.

Sole striker Cassano had run himself into the ground and duly made way for Montella with 27 minutes left.

But the onus was still on Arsenal's back four to bring the ball out and help to create an opening through the packed Roma defences.

They did at least try, but reinforcements were urgently needed and on came Francis Jeffers and Freddie Ljungberg to replace Bergkamp and Wiltord as Wenger resisted the temptation to throw caution completely to the wind.

Arsenal continued to flood forward in numbers. The problem was that they also continued to squander openings in numbers, with Pires and Gilberto both coming close.

It was Roma who should have sealed victory, however, with six minutes left when Montella was left unmarked just six yards out but still managed to plant his header over the bar from Cafu's inviting cross.

Kanu joined the fray but Montella also wasted another half-chance as Damiano Tommassi burst forward.

It is all down the final game. All four teams can go through, but, simplistically, Arsenal still need a draw to progress. They have only themselves to blame.

Teams

Arsenal: Seaman, Lauren (Kanu 88), Keown, Cygan, van Bronckhorst, Wiltord (Jeffers 73), Silva, Vieira, Pires, Bergkamp (Ljungberg 73), Henry.

Subs Not Used: Taylor, Parlour, Stepanovs, Toure.

Booked: van Bronckhorst.

Goals: Vieira 12.

Roma: Pelizzoli, Panucci, Aldair, Samuel, Candela, Cafu, Emerson, Tommasi, Lima , Totti, Cassano (Montella 62).

Subs Not Used: Antonioli, Sartor, Fuser, Cufre, Guigou, De Rossi.

Sent Off: Totti (22).

Booked: Cassano, Samuel, Aldair.

Goals: Cassano 45.

Att: 35,472

Ref: Urs Meier (Switzerland).