Arsenal manager Arsene Wenger has criticised his players for their sloppy defending in the 2-1 loss to West Bromwich Albion.
The Gunners fell to their first league defeat in seven outings to miss out on the chance to climb to the top of the Premier League table on Saturday afternoon.
Olivier Giroud ensured that Arsenal got off to the best possible start at The Hawthorns with his headed goal just after the half-hour mark, but a James Morrison strike and an unfortunate Mikel Arteta own goal gifted the hosts all three points.
Speaking to reporters after the game, Wenger said: "It was a bad afternoon - we missed a penalty, we gave a goal away on set-piece, that is perfect to make your afternoon a nightmare and we missed open-goal chances.
"I believe that West Brom they were strong in the fight and they had one 100 per cent commitment as well and you have to give them credit for that. But overall I felt it dropped a huge blow when we scored and we just had to make sure they didn't come back with a easy goal and that is where we were disappointed today.
"But I cannot be mad at the team because they gave what they could until the last minute but we lost a bit of focus at 1-0 - at 35 minutes we were 1-0 up and then at 45 we were 2-1 down. Our defending on that level was very, very poor."
Arsenal, who are currently fourth in the league table, turn attention to their Champions League commitments in midweek when facing Dinamo Zagreb in North London.