Arsenal just managed to take advantage of an early red card for Hamburg SV keeper Sascha Kirschstein, and the penalty that went with it, to clinch a nervy 2-1 victory in Champions League Group G.
Arsenal, who lost last season's final against Barcelona after Jens Lehmann was sent off early in the game, took the lead in the 12th minute after a similar decision had gone their way.
Robin van Persie skipped past Kirschstein and went down as the keeper stretched out a despairing hand in the 10th minute, although replays suggested there was not much contact.
Gilberto put Arsenal ahead with the spot kick and Tomas Rosicky doubled the lead with a stunning long-range drive in the 53rd minute.
Arsenal seemed to believe it was all over and they almost succumbed to a late Hamburg fightback that saw Boubacar Sanogo pull one back in stoppage time.
Arsenal were bitterly disappointed to lose last season's final after Lehmann was red carded just 18 minutes in. The punishment was worse for Hamburg as Swedish referee Peter Frojdfeldt awarded a penalty as well, much to the fury of the Hamburg players.
Arsenal came into the match with just two points from three Premiership games and they looked nervous in a packed, and extremely noisy, AOL Arena.
A slip from Emmanuel Eboue gave Raphael Wicky a clear run through the middle in the fifth minute and Danijel Ljuboja then cracked a shot just wide.
The game turned when Arsenal, missing injured French striker Thierry Henry, counter-attacked down the left and Emmanuel Adebayor fired over a fantastic cross to Van Persie on the right.
The Dutchman turned the goalkeeper effortlessly and went down as he prepared to shoot from a tight angle.
Lehmann did well to paw away a Guy Demel cross and prevent Sanogo scoring late in the first half and the German also had to save from Ljuboja.
Rosicky's trademark blast from well outside the area briefly shocked Hamburg but they almost pulled one back when Piotr Trochowski cracked the bar late on.
With a minute of stoppage time gone, David Jarolim surged through on the left and pulled the ball back for Sanogo to cap a good display with a neat finish.
It was the first Champions League goal conceded by Lehmann since Arsenal played Bayern Munich in the first knockout round of the 2004-05 season and Arsenal were lucky it did not prove costly.
