Jack Clifford looks set to miss England's November internationals after the back-row suffered a suspected dislocated shoulder in Harlequins' Premiership victory over Sale Sharks.
Clifford left the field with a sling to support his right shoulder late in the first half of Quins' 42-26 bonus-point win at The Stoop on Friday.
The 24-year-old missed England's tour of Argentina following surgery on the same shoulder in April and his latest setback is expected to keep him out of the Tests against the Pumas, Australia and Samoa next month.
Clifford was called up for a recent England training camp as a replacement for Billy Vunipola (knee) and his injury is another blow for Eddie Jones.
"It looks as if [Jack has] dislocated his shoulder" Quins director of rugby John Kingston said.
"It's frustrating for him. On Thursday night we had five players in question, two missed out, three got in – he was one. He had [painkillers] to get him out there in the first place and it's disappointing because he was playing ever so well.
"It's too early to say how long he'll be out."