Arsenal manager Arsene Wenger was delighted with his side's 3-0 victory over Birmingham at St Andrew's.
Wenger revels in victory
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A Robin van Persie free kick and Samir Nasri's 13th goal of the season put the visitors in control before an own goal from Roger Johnson added to City's misery.
The Gunners remain in third spot, two points adrift of Manchester United and Manchester City, after a sixth away success of the season.
"I am delighted because we have shown physical qualities, we were up for the challenge and mentally as well we kept our calm,'' Wenger said. "We kept faith in our game, that we could put the ball down and play our game. I feel we have had a great performance."
Van Persie said: "Birmingham has a great side, they work unbelievably hard and have got points from big games. We knew that and everyone worked quite hard for each other and we got some good goals.''
Asked about the debatable free-kick from which he scored, Van Persie insisted: "There was contact before, that's why I was out of balance and went down. It was a clear free-kick."
Birmingham manager Alex McLeish, whose side dropped into the bottom three after results elsewhere, felt key decisions went against his side.
"Decisions can change games and we feel aggrieved at not getting a penalty in the first half when he (Van Persie) led with his arm,'' McLeish said. "How the officials can't see that ...You need a decision like that against the top sides.''
However, McLeish conceded Van Persie probably had been fouled for the free kick from which he scored the opening goal.
"They do go down easily at times the foreign players, but when I've seen the replay maybe he was taken off balance by one of our defenders,'' McLeish said. "We were a bit sloppy in the first 15 minutes and gave away a few free-kicks that maybe weren't but got punished with one that probably was.''
Asked if he was surprised to be in the relegation zone after finishing ninth last season, McLeish added: "I've never taken anything for granted, it's very much still development for this club and a top-17 finish for this club would be the target.''