Be careful what you wish for, Thomas Vermaelen, as Arsenal still have plenty to learn

Given the absence of captain Cesc Fabregas through injury, last night's emphatic scoreline was impressive and it has convinced the Belgian that his side can bridge the gap against the Premier League's top two should they be drawn against either in Europe.

Vermaelen said: "It's possible we can play them in the quarter-finals but it is just a different game. Maybe we can learn from the games we've played against Chelsea and United.

"Maybe we can learn those things and get on with it in the next games. You can never be afraid of anyone. It's always a good game when you face United and Chelsea — you enjoy it when you play good teams.

"Maybe, we will have the last laugh. You have to focus every game and we will see where we are at the end of the season. We can win this
competition. Otherwise I wouldn't be stood here."

That may be true, but having demonstrated once again why Arsenal are better suited to the technical challenge provided by European opposition, Arsene Wenger must hope the draw for the quarter-finals is kinder to his young players than Vermaelen might wish.

Wenger's team underlined their Champions League credentials in some style, gloriously confirming his own belief that in recent seasons they have looked far more effective on the European stage when facing teams from outside the Premier League.

United and Chelsea have both knocked Wenger's men out of the Champions League in recent seasons and one suspects most Arsenal fans would be happy to avoid them in the last eight.

Wenger boldly declared the chance of playing either of the two clubs would give his team "the chance to show what we can do against them".

Brave words! Arsenal still have a bit to prove against the Continent's top clubs — and a lot to prove against the top two in England.

In most of the last six seasons, Wenger's team have played with vision, endeavour and attacking intent and looked potential European champions until they came up against elite opponents.

The secret of success at this level is producing quality football to order. In 2004, for instance, Arsenal served up high-class performances on their travels — including that 5-1 win over Inter in Milan — but were beaten by Chelsea in the quarter-finals — before Liverpool knocked them out in 2008 they had beaten AC Milan in Italy.

No one can question Arsenal's attacking prowess but rival coaches Sir Alex Ferguson and Carlo Ancelotti have shown they have plenty of ideas about how to break down their defence.

There were times last night when Arsenal's unfolding victory looked threatened by defensive indecision. Their progress to the last eight looked in peril, for instance, when Samir Nasri cleared from under the Arsenal bar in the 59th minute.

Arsenal were leading 2-0 by then — 3-2 on aggregate — and it was Nasri, rather than any defensive improvement, that swung the game decisively in their favour.

Just as Porto threatened to get back into the match, Nasri plunged into their penalty area, wriggling past three defenders before shooting into the net. The goal summed up Wenger's attacking philosophy.

Another outstanding strike, from Emmanuel Eboue, and the late penalty from Nicklas Bendtner made it a memorable night.

Technical superiority is all well and good but you also have to be organised and resilient and able to overcome setbacks. Last night they did just that, overturning a first-leg deficit for the first time since Pat Rice was playing.

Wenger's loyal assistant was captain when Arsenal last recovered from a first-leg defeat in Europe — against Hajduk Split in 1978-79.

Sadly, I remember it all too well. Arsenal were knocked out by Red Star in the next round.