Hull Kingston Rovers prop Johnny Walker has been ruled out for up to eight weeks with a knee injury.
Walker suffered ligament damage on Friday during Hull's 30-10 defeat to Castleford Tigers in the Super League.
"It's not the knee that he's had trouble with in the past, it's his other one, and it looks as though he'll be having eight weeks on the sidelines," coach Craig Sandercock is quoted as saying by Sky Sports News.
Hull continue their Super League campaign this Friday when they travel to St Helens.