Arsenal boss Arsene Wenger has conceded that his side were poor in all areas of the pitch in their 2-0 defeat to West Ham United.
The Gunners lost their Premier League opener as strikes from Cheikhou Kouyate and Mauro Zarate guided the Hammers to the three points at the Emirates Stadium as the home side struggled for intensity.
Wenger told BBC Sport: "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.
"We know fitness wise, West Ham were ahead of us, they had already played competitive games. You never get the same intensity. Well done West Ham. We will respond to that accident. We bought and still lost the game today. We listen to people but we have to focus on the quality of our performance.
"You are never surprised in the Premier League. It is better if we don't talk too much and continue to work hard. 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."
Arsenal face Crystal Palace in their next Premier League clash at Selhurst Park next Sunday.