Manchester City manager Roberto Mancini has admitted that his side should have finished Arsenal off in the second half of Sunday's 2-0 victory at the Emirates Stadium.
James Milner and Edin Dzeko scored in the opening half an hour for the Premier League champions following an early red card for Gunners defender Laurent Koscielny.
However, they were unable to take advantage of their numerical superiority before captain Vincent Kompany was sent off late on.
"It was a good result for us because to play here is always difficult," Mancini told Sky Sports News. "Arsenal are a really strong team. Today, we started the game well with a good attitude, but the sending off made a difference.
"I think that today we should have closed the game in the second half, but we didn't, and that is a big mistake."
The victory saw City close the gap on leaders Manchester United back to seven points.