Wilshere was forced to come off after only seven minutes of the pre-season match after taking a kick on the ankle and Gunners manager Arsene Wenger doesn't expect the teenager to be back in action for a week.
The 19-year-old has an ankle inflammation and, although Wenger hopes he will recovery within a few days, he admitted he wouldn't play for England if he cannot feature in Arsenal's friendly against Benfica next weekend.
That would be a blow to England coach Fabio Capello, who plans to build his midfield around Wilshere and is already without Steven Gerrard and Theo Walcott for the clash against Holland.
"The England game is on August 10 and I don't know whether he will be available. They told me he might be out next week," Wenger said.
"If he is out next week, he will not play against Benfica so he will certainly not play for England.
"They say he might be out for the whole of next week because he has an ankle inflammation. But he has not torn anything. It is not very serious.
"He is a quick healer usually and a tough boy so I hope he will be quicker than the medical predictions."