Arsenal winger Theo Walcott has been ruled out for up to six weeks with the ankle injury picked up while on England duty.
The 21-year-old was stretchered off during England's 3-1 Euro 2012 qualifying victory over Switzerland in Basel on Tuesday night after taking a blow to his ankle.
Walcott was injured in the build-up to Wayne Rooney's opening goal and scans have now revealed the extent of the damage.
"The tackle looked quite bad," manager Arsene Wenger told the club's official website.
"When you see how it turned his ankle I thought it would be three or four days or it would be four to six weeks. Unfortunately it will be four to six weeks.
"We had some good news about the scan because at some stage we were scared it could be worse.
"But overall it is a question of patience and rehabilitation."
Walcott had been in sparkling form during the opening weeks of the new season after scoring four goals in three appearances.
He now joins fellow ankle injury victim Robin van Persie on the sidelines after the Netherlands striker was ruled out for a similar length of time last week.
However, Wenger has revealed some timely good news following confirmation that Samir Nasri has recovered quicker than expected from knee surgery and the France midfielder could be involved when Bolton Wanderers visit the Emirates Stadium on Saturday.
"If needed I will integrate him in the squad for Bolton but for sure he will be back for our first Champions League game against Braga," added Wenger.