Wigan Warriors back-rower Joel Tomkins could be ruled out of action "indefinitely" with a knee injury, says head coach Shaun Wane.
Tomkins, 29, has played nine Super League games in 2016, but missed the 26-6 victory at Catalans Dragons in Perpignan on Saturday.
The England player is set for a scan on the problem, and may need an operation.
"Joel is struggling with his knee, that's not looking good," said head coach Shaun Wane.
Wane's side take on Wakefield on Friday and back-rowers Macauley Davies and Kyle Shelford could make their debuts.
Shelford is the son of late former Wigan player Adrian Shelford, who played 83 times during the 1980s and 1990s.