Arsene Wenger branded Wojciech Szczesny’s sending-off as the moment that “killed the game” after Arsenal’s 2-0 home defeat to Bayern Munich.

The Gunners goalkeeper was controversially red-carded late in the first half for tripping Arjen Robben – and the remaining 10 men were unable to prevent Bayern from easing to victory in their Champions League first leg tie.

“I think our keeper went for the ball, he maybe misjudged the situation, but there was no clear desire to make a foul,” said Wenger. “He touched Robben, who made a lot of it.

“Overall I felt Bayern made a lot of every single contact. We are not used to that in England – fouls were given that are not given in the Premier League.

“The referee made a decision and it killed the game. Until then it was top quality and in the second half it was one-way traffic – it was boring for the neutrals.

“I just feel frustrated. The game delivered what it promised at the start and in the second half, because of that, it was not the same game – it was similar to what happened at Man City [against Barcelona].”

Arsenal squandered a golden opportunity to open the scoring in the eighth minute when Mesut Ozil was brought down by Daniel Boateng inside the penalty area.

Although Ozil’s spot-kick was saved by Bayern goalkeeper Manuel Neuer, the Gunners more than held their own until Szczesny was ordered off by referee Nicola Rizzoli, who also awarded a penalty.

David Alaba also missed from the spot, but Bayern made the most of their numerical advantage after the break and went ahead with a curling finish from Toni Kroos in the 54th minute.

The European champions were utterly dominant and replacement keeper Lukasz Fabianski was called into action on several occasions before Bayern substitute Thomas Muller made it 2-0 three minutes from time.

That meant that, for the second year running, Arsenal will go to Bavaria with a two-goal deficit – and Wenger conceded that a successful penalty from Ozil could have led to a very different outcome.

“We needed to score that penalty because we had three good chances at the start of the game and you could see Bayern were on the ropes,” added the Gunners boss.

“Yes, Ozil was affected by it. He wanted to do so well, but you could see that five or 10 minutes later he was still shaking his head – it had a huge impact on his performance.

“But it isn’t over, because we will fight until the end.”

The second leg takes place in Munich on Tuesday March 11.