Arsene Wenger has described Arsenal's 2-0 loss to West Ham on the opening day of the season as "an accident", and expects an instant response from his crestfallen side.
The Gunners entered Sunday's Emirates Stadium encounter as heavy favourites for the win, but goals in either half from Cheikhou Kouyate and Mauro Zarate saw the Hammers take all three points back with them across London.
This, despite Wenger's men enjoying the lion's share of possession, as well as peppering Adrian's area with 22 shots over the 90 minutes.
"We will respond to that accident," said the Frenchman in the aftermath of their defeat.
"The players were maybe too nervous and put too much pressure on themselves. Today we have been hurt mentally and it is a good opportunity to respond."
He added: "We were not convincing offensively or defensively. I knew it could be a tricky game, if you can't win the game, make sure you don't lose it."