LONDON (AFP) - Arsenal will have to do it the hard way if they are to advance in the Champions League after being held to a frustrating 0-0 draw by AC Milan in Wednesday's last 16 first leg.

Arsene Wenger's side found it impossible to breach Milan's resolute rearguard despite dominating most of a tense tie at the Emirates Stadium.

This was billed as a battle between Arsenal's emerging young prodigies and Milan's aging maestros. It was Carlo Ancelotti's old stagers who finished more satisfied after giving a masterclass in the art of defending.

A score-draw in the San Siro in three weeks time would still be enough to send Arsenal through, but that will be a daunting task against the reigning European champions.

Wenger was convinced the challenge of facing Milan would guarantee there was no hangover from Saturday's FA Cup thrashing at Manchester United. He could have few complaints about their effort, but composure was the missing element.

All Wenger's big guns were available again but there was an early blow for the hosts when Kolo Toure had to come off after blocking Alexandre Pato's shot.

Milan have found it hard to sustain any consistency in Serie A this season, leading some to suggest Ancelotti's stars were finally losing their lustre.

But the Rossoneri have a knack of rising to the occasion on European nights and they were determined not to allow themselves to be flustered by Arsenal's youthful verve.

Paolo Maldini served notice of Milan's intent with a glancing header that Jens Lehmann palmed to safety.

After earning plaudits for winning with style in the Premier League, this was the acid test for Arsenal. They were far from overawed but it was never going to be easy to crack Milan's battle-hardened defence.

Cesc Fabregas's perfectly-weighted pass gave Emmanuel Adebayor the chance to surge clear of Kakha Kaladze but the Togo striker scooped his shot over.

Emmanuel Eboue gave Maldini an embarrassing moment as his neat trick dumped the Italian legend onto turf but Mathieu Flamini's drive was straight at Australian goalkeeper Zeljko Kalac.

Arsenal finished the first half in the ascendancy and they were quick to seize the initiative after the break.

With Italy defender Alessandro Nesta limping off, Wenger's side were suddenly able to find more gaps in the Milan back-four.

Eduardo and Fabregas combined in a flowing move to set up Eboue, only for the Ivorian to drag his shot wide.

Adebayor had the the ball in the net moments later but he had strayed offside and the effort was ruled out.

Kalac was playing with a dislocated finger but the Australian keeper showed no sign of being hindered as he brilliantly tipped over Eduardo's rising strike.

Kaka is usually Milan's creative fulcrum but he found it hard to function in the midfield maelstrom. The Brazilian did manage to slip a pass to Massimo Oddo, who shot wide when he should have at least hit the target.

Fabregas fared little better when Nicklas Bendtner's deflected pass gave him a clear sight of goal.

Arsenal persevered until the end but the Italians had imposed their will to such an extent that a winner looked increasingly unlikely.

Kalac saved from Fabregas again and Adebayor hit the bar in stoppage time as Milan's old heads held on.