The Gunners failed to break down Cardiff’s defence and create any clear chances in the first half.
Walcott had the best chance for Arsenal, side-footing a shot over the bar when a gap opened up between two defenders. Lukas Podolski then failed to react quickly enough to make the most of a Walcott pass across goal, and Jack Wilshere had a penalty attempt turned down.
Cardiff threatened occasionally, with Jordon Mutch shooting from close range on a rare break, but Wojciech Szczesny saved with his legs.
Arsenal got closer in the second half. In the space of five minutes, Jack Wilshere fired a shot against the post, and Per Mertesacker headed wide twice.
With a couple of minutes left, Bendtner reacted quickest to a David Marshall save, and blasted the winner high into the net.
Two minutes later, Walcott chipped the advancing Marshall to seal the victory.
PRE-MATCH - Ole Gunnar Solskjaer attends the match as Vincent Tan’s guest.
13’ - WALCOTT MISS - Walcott slides to reach a Wilshere cross but hits the side netting.
27’ - WILSHERE PENALTY APPEAL - Gary Medel attempts to trip Wilshere in the box, but the Arsenal midfielder’s extravagant tumble doesn’t help his appeal.
28’ - MUTCH CHANCE - Cardiff break through the middle and Mutch fires his shot from a tight angle at Szczesny’s legs.
31’ - ANOTHER WALCOTT CHANCE - Santi Cazorla pulls the ball back for Walcott on the edge of the box, but his shot is wide of the post.
64’ - WILSHERE SHOT - An excellent turn into the box, Wilshere shoots fiercely at goal but hits the post.
67’ & 68’ - MERTESACKER HEADERS - Unmarked on both occasions, Mertesacker sends an easy header wide of the goal.
88’ - BENDTNER WINNER - Marshall beats away Sagna’s back-post header, but the Danish striker sends the rebound into the roof of the goal.
90’ - WALCOTT GOAL - Walcott collects Wilshere’s neat flick and chips the advancing keeper to settle the match.
Olivier Giroud demonstrates his importance: It is more a comment on the lack of alternatives than his own quality, but Arsenal struggled to focus their attacks in the box without their usual striker to aim for. If he’s not back to full fitness soon then Arsenal desperately need reinforcements.
MAN OF THE MATCH
Jack Wilshere (Arsenal): The whole side underperformed in the first half, but as Wilshere’s influence grew, he created chances, hit the bar, and then set up the second goal for Theo Walcott.
Arsenal: Szczesny 6, Sagna 7, Mertesacker 6, Koscielny 6, Monreal 6, Arteta 6, Flamini 6, Wilshere 8, Walcott 7, Cazorla 5, Podolski 5. Subs: Vermaelen 6, Rosicky 6, Bendtner 7.
Cardiff City: Marshall 6, McNaughton 6, Caulker 6, Turner 6, John 6, Whittingham 5, Medel 6, Kim 6, Noone 6, Mutch 6, Campbell 6. Subs: Gunnarsson 6, Cowie 6, Maynard 6.
THE MATCH IN A TWEET