Liverpool, who had been on a seven-game unbeaten streak, had been hoping to build on their win over bitter rivals Everton as they desperately try to cling to the top four spot, but it was Wenger's Gunners who were the more impressive on the night, with Abou Diaby heading Arsenal's winner 18 minutes from time at the Emirates Stadium.
There was also late controversy as Liverpool were denied a penalty in the dying moments of the game after ref Howard Webb failed to spot a blatant hand ball from Arsenal skipper Cesc Fabregas while Steven Gerrard took a free kick.
Two goals by France's Louis Saha (pictured at centre) kept the title race wide open as leaders Chelsea lost 2-1 to Everton on Wednesday. Elsewhere, Manchester United were held 1-1 at Aston Villa and Arsenal beat Liverpool 1-0 to keep up the chase.
Source: ReutersArsenal's Abou Diaby (L) celebrates
with teammates Theo Walcott (C) and Cesc Fabregas (R) after scoring
against Liverpool- WATCH the video (1:38)
Louis Saha scored twice and missed a penalty as Everton came from behind to beat Chelsea, while Abou Diaby headed Arsenal's winner 18 minutes from time at the Emirates Stadium.
Aston Villa took the lead against United when Carlos Cuellar scored after 19 minutes but the visitors equalised four minutes later through a James Collins own goal before playing for the final hour with 10 men after Nani was sent off.
With 26 matches played, Chelsea have 58 points, Manchester United 57 and Arsenal 52. Liverpool are fourth on 44.
Tottenham Hotspur lost ground in the race for fourth place, after a 1-0 defeat at Wolverhampton Wanderers, who moved out of the relegation zone along with West Ham United following their 2-0 win over Birmingham City at Upton Park.
Hull City lost 1-0 at Blackburn Rovers, slipping from 15th to 17th, just a point above the relegation zone.