Arsenal cruised into the knockout stages of the Champions League with a comfortable 5-1 win over a shell-shocked Rosenborg side at Highbury.
The Gunners, without suspended captain Patrick Vieira, needed to win to ensure qualification and set about their task from the first whistle, taking the lead with just three minutes on the clock.
Cutting in from the left, Jose Antonio Reyes latched onto Dennis Bergkamp's neat pass just inside the area, before turning centreback Torjus Hansen inside out, and slotting the ball home from a tight angle.
Rosenborg were stunned by the early goal and Arsenal piled on the pressure as Reyes, Thierry Henry and Robert Pires marauded forward, all three seemingly identifying the hapless Hansen as a weak link.
The visitors had their first chance of the match on 20 minutes when Arsenal shot-stopper Manuel Almunia had to turn Harald Brattbakk's volley around the post, but that effort served only to rouse Arsenal, who doubled their lead minutes later.
Henry ran onto Flamini's midfield block before leaving Hansen for dead and lifting his shot over the on-rushing Johnsen and into the back of the visitor's net.
Cesc Fabregas was next on the score-sheet as he became the Gunner's youngest ever European goalscorer with his 29th minute goal.
The 17-year-old showed maturity beyond his years as he brought down Pires' pass inside the area before lifting the ball past Erik Hoftun and twisting back inside to blast a half-volley past Johnsen.
To their credit, Rosenborg refused to crumble and three minutes after Roar Strand had hit a header against the woodwork, they pulled a goal back with the help of a double blunder from Almunia.
Having come for but dropped Brattbakk's free-kick, the Spanish keeper who was playing in place of the out of favour Jens Lehman, then contrived to push Hoftun's hooked shot into his own net.
Any fears of a Rosenborg comeback were erased four minutes before the interval when Bergkamp's pass put Henry into a one-on-one with Johnsen, whose attempt to claim the ball succeeded only in up-ending the French striker for a penalty that Pires converted.
The second half failed to live up to the heights of the first, with Rosenborg seemingly content to keep the scoreline down and Arsenal, at times, looking like they were playing a practice match.
Robin van Persie got his name on the score-sheet six minutes from time when he collected Reyes's neat pass and lifted the ball over Johnsen to wrap up an impressive display.
