Daniel Heckenberg joins Louie McCarthy-Scarsbrook on the sidelines
Harlequins have lost a second prop through injury with Daniel Heckenberg ruled out for up to six weeks with a dislocated shoulder.
The 28-year-old, who underwent shoulder surgery last June, suffered the injury in training.
He joins fellow front-rower Louie McCarthy-Scarsbrook on the sidelines after he sustained a broken wrist in Friday's defeat at Leeds.
The 22-year-old will be out of action for up to four months.
Quins coach Brian McDermott told BBC London 94.9: "Daniel can return in four to six weeks, but how strong his connective tissue is going to be nobody knows.
"It's a case of patching him up and sending him back out there."
McCarthy-Scarsbrook hopes to be part of the England squad that will travel to Australia for the World Cup in October.
"He's been looking like a seasoned player in the last three or four games and he's just starting to take shape," said coach Brian McDermott.
"He was also looking good for a mid-season international spot, so it's disappointing for him that this may rule out that opportunity.
"Every club gets an injury crisis, and it's now up to our young players to step up to the mark and take their opportunity to show us what they can do."