England full-back Delon Armitage should discover the severity of his shoulder injury tomorrow morning.
Armitage left the pitch with a suspected dislocation of his left shoulder in the final quarter of London Irish's 40-10 Guinness Premiership victory over Gloucester yesterday.
The 25-year-old, who played in every one of England's matches last season after making debut in November, will undergo a scan today.
A England statement read: "Further to an injury sustained to his left shoulder during the Guinness Premiership match between London Irish and Gloucester Rugby yesterday, Delon Armitage will have a scan today and the results will be available this evening.
"Delon will then see a specialist tomorrow morning to review the results of the scan. Once that consultation has taken place a further announcement will be made."
London Irish head coach Toby Booth was reluctant to give a date for Armitage's return but the typical recovery time for a dislocated shoulder is six to 12 weeks.
Even at the lowest end of severity his participation in England's opening November international against Australia is under threat, while he could also miss the Tests against Argentina and New Zealand.
Armitage was England's outstanding player last season, coming from nowhere to make his Test debut against the Pacific Islanders in November - starting a run of 11 caps that produced five tries.
England can ill afford to lose arguably their most dangerous runner, not least with fly-half Toby Flood already ruled out for the autumn schedule and Lions centre Riki Flutey also a doubt.