Harlequins skipper Nick Easter is an injury worry for the final Pool rounds after damaging a knee in his club's 10-7 Guinness Premiership win at Worcester.
The number eight has played a major role in the recent resurgence of Harlequins and was a key player in England's World Cup campaign and will be needed by his team if they are to haul themselves from the foot of Pool 3.
They have won just one of their four games so far this term, despite being in the top half of the Guinness Premiership all season.
And Quins coach Dean Richards now faces a nervous wait until the extent of the forward's injury is known.
"Nick has twisted his knee," he said. "We'll see how he is and we'll make sure he has a scan in the next couple of days."
Victory ensured the London club remain in the hunt to play in next season's Heineken Cup, but Easter's injury took the shine off the win.
Quins play Cardiff Blues in Round 5 and finish by hosting Stade Francais in Round 6.
