It took this trial of a tie to invigorate Arsenal. No one can yet say that all is well with the club, but its players and supporters were in good heart on a night that saw them go through once more to the group phase of the Champions League. On this occasion, no one could allege that they are too well-bred to struggle through a moment of crisis.

Indeed, a penalty save from Wojciech Szczesny was needed to deny Udinese a 2-1 lead. Following the 1-0 win London, the tie had been brought level on aggregate when Antonio Di Natale opened the scoring at the Stadio Friuli with a well-judged header in the 39th minute. On this evening, there was no melancholy or slippage in morale.

Instead, Arsenal reacted with goals of their own. Their second contained the sort of individual impact from Theo Walcott that sometimes seems to have deserted him since his first, instinctive days with the club.

Udinese did rally in spells but Arsène Wenger's players knew their own worth and had none of the self-destructive tentativeness that has kept them from collecting a trophy since 2005. Di Natale was denied when Szczesny showed the necessary defiance in the 59th minute by leaping to his right to reach a penalty awarded following a handball by Thomas Vermaelen.

Had Udinese broken through then, they would have led 2-1 on their own pitch and the tone of the game would have been transformed, with the home side sensing glory. A qualifier cannot confirm that all is well, but Wenger's side did meet this test boldly. The outcome may improve the mood of a squad bound for Old Trafford in the Premier League at the weekend.

The instant in the match with Udinese that will be recalled most vividly may not be Walcott's exchange of passes with Bacary Sagna on the halfway line before outpacing Mehdi Benatia and tucking the ball past the Udinese goalkeeper, Samir Handanovic, in the 69th minute.

The outcome had looked most in question when the Serie A club moved 1-0 in front. At that stage the contest was being conducted with passion, enterprise and speed.

Udinese had the better of it then. They were in a frenzy of ambition and Di Natale had eased in to hit the post in the 23rd minute, following a ball from Mauricio Isla. The captain and striker is still celebrated, at 33, as the most impressive figure at the club. He is a veteran yet fended off the heat and humidity as well as any stripling. Arsenal stuck to those who literally are young.

Wenger is sometimes criticised for being so ready to pick inexperienced players. At this stage in a fascinating career, though, he is not for changing.

The 19-year-old full-back Carl Jenkinson made his competitive debut from the bench in the first match with Udinese and has started the two subsequent fixtures, including this contest.

He was accommodated on the right, his best position, even though that meant Sagna switching wings to play left-back. Emmanuel Frimpong, a midfielder of the same age, also had the new experience of being on the pitch at kick-off in a Champions League match, although he was replaced at the interval.

Frimpong had initially been eye-catching and so, too, was the boldness with which Arsenal at least sought to pummel Udinese at the start. Indeed it took a little time for Francesco Guidolin's men to exercise a semblance of the control they would have anticipated. At that juncture, it looked as if the side was wholly at ease with itself.

It would be wrong to pretend that Arsenal's difficulties are being exaggerated when one fine creator in Samir Nasri has just signed for Manchester City and Cesc Fábregas, an even greater midfielder, had already left for Barcelona. Even so, this match was grasped as an opportunity for the club to strike an encouraging note. Reaction to the first leg, won 1-0 by the hosts, was coloured by the general troubles that Wenger has to address.

At least a possible touchline ban was not imposed on the Arsenal manager by Uefa for this fixture, despite the charge that he had been in contact with his coaches while serving a ban that confined him to the stand for the first-leg at the Emirates.

The manager was close to the action here and sought to alter it with introduction of a creator, Rosicky, for the second-half. The Czech Republic international replaced the inexperienced Frimpong.

The terms of the contest had to alter for Arsenal. It was Robin Van Persie who gave the fixture that necessary jolt, after 55 minutes, by finishing after excellent work on the left by Gervinho when he set up the Dutchman on the edge of the six-yard box.

Peace, of course, could never fall quite so easily on an encounter of this consequence, but Walcott's goal made Udinese understand that their cause was lost.

Economics now return the fore. Arsenal, with a Champions League campaign to come, are assured of the usual revenue. It only remains for Wenger to buy new players they still need regardless of this victory.

There is much to be done in the remainder of this month