Arsenal boss Arsene Wenger has attempted to explain their collapse against Bayern Munich

The Gunners went in to the half-time break on level terms after Alexis Sanchez cancelled out Arjen Robben's stunning opener.

Laurent Koscielny limped off on 49 minutes and that sparked a stunning collapse that saw the hosts run riot.

Robert Lewandowski and Thiago struck in the next seven minutes and Wenger believes his side lost their heads after the crucial third.

"I think it was difficult to swallow the two goals after minutes 53 and 56," Wenger said.

"I think we have to analyse that, but it looks like that from outside.

Laurent Koscielny's injury was a key turning point

"We lost our organisation, we lost our centre back.

"But after the third one it was a combination of [mentality] and organisation.

Arsene Wenger believes Arsenal folded after Thiago hit No.3

"Before that, we controlled them quite well."

Arsenal host the return leg on Tuesday, March 7.