Wenger called Arsenal’s second%u2011half collapse, which including conceding three goals in 10 minutes, “a nightmare” before cutting short his post-match press conference.
Arsenal now face the prospect of going out of the Champions League at the first knockout stage for the seventh consecutive season.
“The real problems were after the third goal,” Wenger said. “We lost our organisation and we looked vulnerable from that moment onwards. The last 25 minutes was a nightmare for us. We looked like we had no response. We collapsed.”
Arsenal need to win 4-0 in order to progress in the return tie in London on March 7.
Oh, dear. Arsene!
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Wenger, though, refused to use the loss of Laurent Koscielny through injury as an excuse.
“Overall I must say they [Bayern] are a better team than us,” he said. “They played very well in the second half and we dropped our level. I do not look for excuses.
“If you asked if I would have loved to keep Koscielny on the pitch, I would say yes. But no matter what we say now, it will be turned in a way that’s detrimental to us because we had a very negative result.
“It looked like we lost our organisation. Not only did we lose our centre-back, but we had a combination of mental and organisation problems.”
Wenger’s opposite number Carlo Ancelotti, meanwhile, praised Spanish midfielder Thiago Alcantara after a sparkling display that included a brace.
"He played very well and scored two goals," Ancelotti said.
"It was a perfect performance."
The Italian also refused to accept Bayern were already in the last eight.
"The result is important, but we have another game in London," Ancelotti said. "We need to show the same passion."