LONDON — Arsenal boosted its Premier League title hopes and dented Manchester City's with a 2-1 victory over its rival at the Emirates Stadium on Monday.
Theo Walcott gave Arsenal the lead with a ferocious low strike from the edge of the penalty area in the 33rd minute, and Olivier Giroud doubled the advantage with a clinical finish on the stroke of halftime.
Yaya Toure pulled a goal back with a first-time, left-footed strike eight minutes from the end, but City could not find an equalizer.
The win moves second-place Arsenal to 36 points, two behind leaders Leicester on 38. City is third on 32.
"For us it was a vital game," Arsenal manager Arsene Wenger said. "It is too early to say to win the league but it strengthens our belief. You earn the right to win these games and it is important to realize you must fight for every game."
In the only bad news of the night for Gunners fans, Alexis Sanchez was scheduled to be named as a substitute against City but Wenger said he now expects the Chilean to return on Jan. 10. The striker has had a setback in recovering from a hamstring injury which has kept him out since Nov. 29.
City welcomed striker Sergio Aguero back to the starting lineup for the first time since November and the first half was an intriguing encounter at times, with both teams passing the ball around confidently.
Arsenal probed patiently against City's defense, which in turn looked to build counterattacks by swiftly playing the ball to creative midfielders David Silva and Kevin De Bruyne whenever possession was recovered.
It was that tactic from Manuel Pellegrini's side which should have yielded the opening goal, moments before it fell behind.
City swept forward on the break in the 32nd, Aguero flicking the ball into the path of the onrushing De Bruyne, who had surged far beyond his marker, Nacho Monreal.
As De Bruyne closed in on goal, he had Silva unmarked to his left, who would have had a simple tap-in. Instead, he decided to shoot and his effort rolled the wrong side of the post.
It turned out to be a decisive moment in the match as Arsenal ruthlessly punished the miss a minute later.
Mesut Ozil brought the ball into the final third and played a low pass into Walcott, who shifted onto his right foot and whipped a shot low into the far corner, beyond the reach of outstretched City goalkeeper Joe Hart.
The second came on the stroke of halftime. Ozil, the king of assists, was again the provider by steering a pass neatly into the stride of Giroud, who drilled a left-footed shot through Hart's legs and into the far corner for his 10th league goal this season.
Joel Campbell missed two chances to seal victory early in the second half, shooting over from eight yards before being denied by Hart's foot when through one-on-one.
But Arsenal continued to push for a third, and Aaron Ramsey almost capped a sublime passing interchange from Ozil and Campbell on the hour mark. Hart was quickly off his line to smother the opening.
City managed to pull one back with a superb lofted strike from Toure after receiving a pass from Bacary Sagna. It ensured a nervy finish, but Arsenal held firm.
"In the second half we took some risks, we continued going for the game," Pellegrini said. "We did better than Arsenal but we didn't win and that is all that matters. We didn't deserve to lose the game."