CSKA Moscow 1 Arsenal 0: Arsenal slipped to their first Champions League defeat of the season after Daniel Carvalho's free-kick gave CSKA Moscow a Group G victory.
The hosts netted the winner in the freezing Russian capital after 24 minutes when Carvalho blasted through the Gunners wall from just short of 25 yards to give Jens Lehmann little chance.
The Russian champions almost doubled their lead moments later when Wagner Love swept in Carvalho's left-wing cross at the near post - only for the celebrations of the Russian champions to be cut short by the assistant referee's flag.
Arsenal finished the half the stronger but they were unable to make their pressure count with Robin van Persie twice wasting possession when in a threatening position, while Tomas Rosicky's dangerous cross just evaded Thierry Henry on the back post.
CSKA started the second period brightly and but for some excellent defending by Kolo Toure, Johan Djourou and William Gallas, could easily have doubled their lead.
But if the Gunners defence appeared steady, their midfield was looking very much overrun, with the pace and movement of Brazilians Love, Carvalho and Dudu causing no amount of problems to Arsene Wenger's side.
The Gunners brought on Emmanuel Adebayor in place of the ineffective van Persie midway through the second period and soon introduced Theo Walcott for Alexander Hleb and the double change helped them finally exert some pressure on the hosts.
Gilberto soon had the ball in the net with a header but he was rightly flagged offside from Toure's flick, while Justin Hoyte's right-wing cross on the run struck the near post before being cleared to safety.
Henry then produced what he thought was the equaliser with just five minutes left when he chested down the ball and slotted home, but the goal was controversially disallowed for handball with the Frenchman also cautioned for his troubles.
That was to prove the key moment in the match and CSKA were able to hang on to the three points which took them to the summit of Group G ahead of Arsenal.
