Arsene Wenger was rendered ‘clueless’ after his side threw away a three goal lead.
Arsenal Legend Paul Merson claimed that Jose Mourinho would never allow his team to collapsein the same style.
With goals from Danny Welbeck, Alexis Sanchez and Alex Oxlade-Chamberlain, Arsenal seemed set to be going through to the knock-out stages for the 15th consecutive year.
But Anderlect scored three times in 30 minutes to effectively end their chances of topping group D.
And Sky pundit Merson rapped: “I think they’re tactically clueless. How you can be 3-0 up and attacking.
“This is not the first time, this happens a lot of times. It is absolutely clueless.
“For me the manager’s got to get a message on. If you know football you say: ‘Right, let’s stop here. Let’s have two banks of four, let’s leave two up front and we’ll go from there. Let them break us down’.
“I bet you Jose Mourinho hasn’t drawn too many games from being 3-0 up. That tells you everything.”
A shocked Arsene Wenger admitted: “We got punished. A bit of bad luck because the first goal was offside but our defensive performance was not good enough.
“At 3-0 we thought the job was done. It was fatigue as well, they finished stronger and sharper. At 3-0 subconsciously you can think the game is won. Defensively as a performance across the pitch we were very, very poor.
“Am I angry or disappointed? Both. At 3-2 you have to secure yourself and we were not cautious enough.”
Borussia Dortmund’s win over Galatasaray means Arsenal still need only a point from their final two games to reach the last 16.
But captain Mikel Arteta, who went off with a hamstring strain with the score 3-1, said: “It is just not good enough. We missed a great opportunity to finish it off. We have thrown everything away today.”
Anderlecht coach Besnik Hasi added: “Maybe Arsenal thought they were on top and they could get more goals and they could have fun in front of the public. But I think Arsenal are vulnerable defensively.”