Harlequins should discover today the full extent of their England wing David Strettle's latest foot injury.
Strettle has an appointment with a surgeon, after being hurt during Quins' Guinness Premiership victory over Worcester last week.
His recent medical history does not augur well, given he missed last year's World Cup and most of the RBS 6 Nations Championship last season because of foot problems.
Quins rugby director Dean Richards said: "In terms of knowing exactly what the score is, we will wait and see what the surgeon says.
"There is a possibility he might have an operation - I don't know at this stage."
If Strettle, currently part of the England Saxons squad, requires surgery then he looks unlikely to play again before Christmas.
Strettle and his fellow England internationals Danny Care, Mike Brown and Nick Easter all missed Quins' heroic attempt at causing a colossal EDF Energy Cup shock yesterday.
Quins led a star-studded Ospreys side 23-17 in injury time at the Liberty Stadium, only for substitute Tommy Bowe to score a try that fly-half James Hook converted for a one-point win in Pool C.
Ospreys head coach Sean Holley conceded it had been a fortunate escape, after Quins wiped out an 11-point interval deficit to lead through tries by centre De Wet Barry and hooker Tani Fuga - plus Fijian Waisea Luveniyali's 13-point haul.
Holley said: "It was a classic get out-of-jail situation.
"We are making no excuses. We were really tested. But apart from an injury to Sonny Parker (chest), there were no other (injury) problems - just a few bruised egos."
Wales centre Gavin Henson started his first game for six months after recovering from an ankle injury, but none of the Ospreys' sizeable international contingent could make a lasting impact.
Quins fielded a solitary survivor from their win at Worcester - flanker Chris Robshaw - but they outscored Ospreys 20-10 in the second period.
Quins rugby director Dean Richards said: "The boys are very disappointed.
"We didn't have a good first half - we showed the Ospreys too much respect - but then we took it to them in the second half."
The Scarlets made it a clean sweep of Welsh wins during the tournament's opening weekend - following up victories by the Ospreys, Cardiff Blues and Newport Gwent Dragons by defeating Vicarage Road hosts Saracens 26-17.
Scarlets head coach Nigel Davies said: "This competition is something we have targeted, and to start with an away win is great.
"But in terms of performance, there was a lot missing there. We are a new group of people, and there is a lot of work to do."
The RBS 6 Nations Championship 2015 was not poised to go down as one of the more "vintage" Championships, though there was great anticipation as the action headed into its final day. What transpired was something that nobody could foresee: "The Greatest Day in Rugby's Greatest Championship."