Predatory Arsenal progress in style

Arsenal 5 - Rosenborg 1

After arriving in London early to combine the Champions' League with shopping, Rosenborg leave later today having also gift-wrapped Arsenal's passage into the last 16 of the competition. Normally the Norwegians only present the capital with a Christmas tree at this time of year. Here it was a present worth £10m, which is what a relieved Arsenal will accrue from reaching the knock-out stages.

With Panathinaikos beating PSV Eindhoven, Arsenal had the satisfaction of winning Group E having gone into the evening fretting over whether they would simply qualify. Four quick-fire first-half goals against a plainly demotivated opposition soothed the nerves and if Arsenal had continued at full throttle they would have recorded their biggest win in European competition, eclipsing the seven goals they knocked past Standard Liège a decade ago. In the end, they simply equalled their best European Cup score, which came last season in the San Siro, no less, against Internazionale.

As an indicator for Sunday's Premiership encounter with Chelsea this contest provided little, however. It will have injected further confidence into the champions but that will have been diluted by a nervy goalkeeping display by Manuel Almunia. After making a fine early save, turning Harald Brattbakk's fierce half-volley around a post, he dissolved into a bag of nerves to such an extent that a routine late stop was greeted with ironic cheers that will not have gone unnoticed by Arsène Wenger. Almunia was at fault for Rosenborg's goal in not communicating with his defenders, his distribution was poor and, after another fumble, he resorted to punching away corners.

"It is a national debate here when I want to change a player in the team," Wenger said when questioned on his goalkeepers. "At the moment he is playing under such a huge pressure that he is not himself." Which begs the question: can he handle it? Wenger deemed this harsh also and, in the context of such a rout, that was true. But even he prefaced his verdict by talking of this game in conjunction with Sunday's and he leaves himself open to another prolonged selection debate. After last night's events Jens Lehmann may now return, which was clearly not Wenger's plan prior to kick-off.

Wenger was presented with another kind of headache with Fredrik Ljungberg, his most in-form player, dropping out with a migraine. He may not make the Chelsea match. In came Jose Antonio Reyes, who has been struggling, but he received a much-needed boost inside three minutes when he was picked out by Dennis Bergkamp, twisted sharply in the area and coolly drove his shot in off goalkeeper Espen Johnsen. It was his first goal for two months.

It soon became apparent that Rosenborg, who have now lost 15 of their last 16 away ties in this competition, and whose domestic season finished three weeks ago, were mentally, if not physically, on the beach enjoying their three-month winter break. None more so than the defender Torjus Hansen, who was simply woeful. He was at fault for Arsenal's first two goals ­ for the second Thierry Henry ran on, after Mathieu Flamini had won a tackle, to loft the ball over Johnsen with Hansen struggling.

Flamini, just 20, and making his first start for Arsenal outside the League Cup, was providing a promising partnership with 17-year-old Cesc Fabregas, whose first-half display Wenger described as "dominant". On 29 minutes it was the Spaniard who scored the third goal after Robert Pires cushioned a cross into his path. Fabregas steadied himself, shifted the ball in front of a defender and joyfully lifted it beyond Johnsen to became Arsenal's youngest goalscorer in European competition.

Immediately Arsenal were jolted. From a corner Roar Strand's header struck a post and then, from a free-kick, Almunia flapped at the ball and presented it to Erik Hoftun, who drove his shot inside the near post. Damage was done but any chance of Arsenal faltering was extinguished when Bergkamp released Henry. As he rounded Johnsen the goalkeeper caught him with his trailing leg. Pires swept in the penalty.

"Arsenal showed us a level we could not reach," said Rosenborg's newly installed coach Per Joar Hansen. However, he also added, correctly: "We made all the mistakes it is possible to make.

With the game over Arsenal's performance dropped in the second half until Robin Van Persie came on. Desperate to score he saw two left-foot drives screw wide, while Reyes chipped on to the roof of the net, before the Dutchman dinked the ball in for the fifth goal. But even that achievement was tempered by Almunia's late errors. Wenger has a decision to make.

Arsenal (4-4-2): Almunia; Hoyte, Campbell, Touré, Cole (Van Persie, 76); Pires (Owuso-Abeyie, 88), Flamini, Fabregas, Reyes; Bergkamp (Clichy, 73), Henry. Substitutes not used: Lehmann (gk), Senderos, Larsson.

Rosenborg (4-3-3): E Johnsen; Solli, Hoftun, Hansen, Stensaas; Strand (George, 62), F Johnsen, Winsnes (Olsen, 88); Braaten, Helstad (Storflor, 78), Brattbakk. Substitutes not used: Ronningen (gk), Russell, Skjelbred, Tettey.

Referee: S Farina (Italy).