Per Mertesacker headed Arsenal into a half-time lead over 10-man Fulham at Craven Cottage in an opening 45 minutes during which Steve Sidwell was sent off for consecutive games.
Sidwell, who was returning from a three-match suspension following his red card against Queens Park Rangers, was dismissed again on 12 minutes when his forceful lunge caught Mikel Arteta on the ankle.
However, the hosts could not immediately capitalise on their numerical advantage, and instead Fulham were a threat on the counter-attack.
The pacey Urby Emanuelson broke at speed before releasing Dimitar Berbatov, whose attempt to squeeze in a shot at the near post was thwarted by Gunners stopper Wojciech Sczcesny.
Eventually, Arsenal managed to exert some sustained pressure on the hosts, and Olivier Giroud came close to breaking the deadlock when his shot on the turn struck the base of the post.
They snuck ahead just prior to the interval when Theo Walcott, who had previously had an early effort ruled out for offside, swung in a free kick that Laurent Koscielny headed across goal for his centre-back partner Mertesacker to nod in from close range.
