St Helens captain James Roby is expected to miss a month as he is set to undergo groin surgery this week.
The 33-year-old has been in and out of the Saints squad this season due to the injury, making 14 appearances in total.
After Saints’ 23-22 defeat to London on Sunday, St Helens coach Justin Holbrook confirmed in his press conference that Roby will undergo surgery on his groin this week.
He said: “Robes has been struggling with it for a while.
“He’ll get some minor surgery this week so he’ll probably miss four weeks.”
Roby is set to miss upcoming games against Huddersfield, Leeds, Warrington and Hull FC.