Arsene Wenger has seen his pre-season preparations hit by a sickness bug.
Per Mertesacker and Olivier Giroud both missed the friendly with Bayern Munich , Theo Walcott and Aaron Ramsey played despite feeling ill while Sead Kolasinac was sick on the pitch.
Arsenal boss Wenger has put it down to food poisoning and also revealed that his assistant Steve Bould has missed the Chinese leg of the trip after undergoing surgery on a hernia in his neck. Laurent Koscielny is also nursing a back injury.
Wenger, whose side beat Bayern Munich on penalties despite sweltering heat in Shanghai, said: "We had to dig deep and think we will benefit from it. The doctor thinks it is food poisoning.
"Kolasinac was sick as well. Walcott, Aaron, all had a little bit of food poisoning as well.
"Steve Bould has a hernia on his neck and had to do it in Australia and he couldn’t travel. He went home on Saturday. He’s OK. He went home and he’s good."
Wenger’s men did beat the Germans on penalties after Alex Iwobi’s last gasp leveller took it to spot kicks. Sub keeper Emiliano Martinez was the shoot out hero, saving two spot kicks while Petr Cech was man of the match after a string of brilliant saves before going off.
But the sweltering conditions and humidity made it tough for Arsenal and the players have clearly found the intense training sessions difficult in temperatures soaring towards 40 degrees.
Wenger added: "If you ask me is it an ideal way to prepare physically, I say certainly not. Does it have other advantages? Yes, because we can meet fans from all over the world.
"The bonding is easier because we live together for two weeks. On that front it can be positive.
"It was a shock to come from Australia where we were freezing when came out of the plane in Shanghai and we decided to work very hard on Monday and Tuesday and so I was a bit scared that we could have big problems.
"But the real answer will be given by the way we start in the championship."