Arsène Wenger admits his side didn't do their defensive job properly in the 6-3 defeat to Manchester City on Saturday.
Arsenal had the best defensive record in the Premier League going into the game and Wenger was disappointed to see his side lose their discipline.
You could see that the legs were tired and you play Sunday, Wednesday, Saturday morningArsène Wenger
"I'm very disappointed because we didn't do our defensive job as we are used to," Wenger told Arsenal Player.
"We didn't defend well from up front and did not show enough solidarity defensively. That's too easy going.
"We had the best defence until now in the league and to give six goals like we did today is just difficult to accept because we lost our discipline and in the big games and you pay for that.
"The schedule didn't help us, let's be fair as well," he added. "You could see that the legs were tired and you play Sunday, Wednesday, Saturday morning, it's too difficult."Copyright 2015 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source 16 Dec 2013