Arsenal manager Arsene Wenger has admitted that his side suffered a defensive failure against Kitchee but insisted that he has faith in his players.
The Gunners conceded twice against the Chinese side in Hong Kong on Sunday as they were held to a 2-2 draw in their latest pre-season game on their Asia tour.
"I think defensively we looked fragile, especially in the first half," the Frenchman told Arsenal's official website.
"In the second half not so much because we were not challenged. Defensively we have a lot of work to do as a unit to do much better.
"We let everybody play today and some players are not yet at the level of the Premier League. It is a learning process."
Wenger went on to underline the importance of pre-season matches.
"If you don't do it in pre-season then you never do it - you give them a chance to see what is requested at the top level," he explained.
"I played all of the defenders during this tour to see who is ready and who is not. We have Sagna, Koscielny and Mertesacker at home - three experienced defenders."
Arsenal will begin their Premier League campaign with a home game against Sunderland on Saturday August 18.