"The sending-off was an unpleasant surprise and the wrong decision," said Wenger.
"It was not Robin's fault - there was no purpose. He wanted to play the ball. He got a high ball, and never saw the opponent, never looked somewhere else than at the ball - it was an accident. For me, it is never a red card."
"I feel the team needed a win, but I would not have panicked if it had been 1-1 because I feel we are capable of winning in Thun.
"It was not easy, because we played for an hour with 10 against 11, against a team who defends well, and stays at the back - it was difficult. If you look at the number of chances we created, there were not so many because we lacked a man and they did not come out.
"I can understand that, because we are super-favourites. But maybe they missed an opportunity to make a big upset."