Arsenal failed to click into gear at Emirates Stadium and Michu punished the north Londoners for a poor display with two late goals to give the visitors victory.
Wenger’s side have only won one of their last six Premier League games, with the Gunners now languishing in 10th place in the table, 12 points behind leaders Manchester City.
The Frenchman, who was greeted with a chorus of jeers at the final whistle, conceded that his side were poor and that Swansea were worthy winners.
“We were not at our best today and Swansea deserved to win,” Wenger told Sky Sports. “We were guilty because we’ve thrown it a little bit away by being not attentive in the last three minutes and we lost the game.
“It’s a concern because we didn’t create a lot. We were a little bit against the wall and our passing was not sharp or quick enough to create danger.
“We looked jaded, not sharp, and we tried very hard but we maybe lacked a little bit of maturity to keep at least a 0-0. We gave many chances away today.
“It’s a big blow because we wanted to start [December] well and we go now to Olympiakos as well on Tuesday; the games come very quickly. We have to recover and win our next game.”
Asked if an edgy atmosphere at The Emirates had an effect of his side’s display, Wenger replied: “They have an influence but it’s down to us to get the fans behind the team. The way we play has to create that.
“Of course when you lose a game the way we did you can understand that [the fans’ reaction at the final whistle].”
Wenger added: “At the moment we have to catch up [to the title challengers]. I believe we have to find the quality of our game back and what we played today is not the way we wanted to play football.
“It’s more important for us to concentrate on the quality of what we want to do, the vision we have of the game. Today that was not the case.”
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