Perhaps they were sleepy from staying up to late waiting for Santa to arrive, but Arsenal didn't really start playing until going down 1-0 early in the second half, after Szczesny spilled a save right in front of Carlton Cole, who said "Thanks" as he despached the ball into the net. Shortly thereafter, Aaron Ramsey picked up a thigh injury and had to be replaced by Lucas Podolski, who has just returned from injury. And that changed the match completely.
In the first half, a lethargic Arsenal couldn't get anything going, even while holding lots of possession. And Ramsey was among the least sharp of the Arsenal players. For several games in a row now, he's been off the boil, looking more like the weak and indecisive Ramsey of last season more than the brilliantly sharp Ramsey of the first two months of this season. Not that the other Gunners were playing well or anything, but once Ramsey was replaced, the whole team, including its shape, were transformed. Podolski went out to the left wing, and Cazorla took up Ramsey's position in the center, alongside Ozil, which is where he belongs. Arguably, that's Arsenal's strongest central midfield duo (with all due respect to Wilshire and Ramsey). The problem Wenger has is that Wilshire and Ramsey are crap on the wings, and Cazorla is at least better than that. But he has a tendency, when playing on the wing, to come inside, which simply clutters up the middle. Anyway, once Podolski entered the match and Cazorla was allowed to play in his most natural position, the Gunners were transformed offensively.
Theo Walcott, who had an otherwise indifferent game, scored Arsenal's first two goals. The first was a weak shot that most pro goalies would have stopped with ease. The second was on a fine cross from Podolski, who then chipped in with the third goal, which came from Arsenal's nicest offensive move of the game.
Podolski's return from injury at the busiest time of the season, when Arsenal are playing 4 games in 9 days, couldn't have been timed better. But losing Ramsey for any length of time would be problematic. Fortunately, Wilshire is available for the next game away to Newcastle on Sunday. This is where Arsenal's depth in midfield really should pay off. And Podolski's return creates another much-needed goal-scoring threat in addition to Giroud and Walcott.