Perpignan duo Gavin Hume and Henry Tuilagi were hospitalised after the bruising Pool 1 encounter with London Irish on Sunday afternoon.
South African born centre Hume, who has been standing in at fly-half for the injured Nicolas Laharrague and Steve Meyer, was admitted with a suspected broken leg, whilst Tuilagi suffered two broken ribs.
There are yet further concerns that the 31-year-old Samoan may have also suffered kidney damage. Tuilagi will undergo further medical tests to ascertain the extent of the damage,
The loss of Hume means second-string fly-half Cedric Rosalen, who has struggled to find his form this season, is expected to be recalled to the No. 10 jersey for the visit of London Irish this weekend.