Warrington forward Ben Harrison could be out for up to eight months after surgery on his knee, wrist and ankle.
It means the 27-year-old loose forward could miss up to half of the upcoming 2016 season.
The former England international featured in 29 games for the Wolves last season, scoring two tries.
"He needed it. I think we all saw he was struggling through and hampering the quality of work he was able to put out," said head coach Tony Smith.
"It's a six, seven, eight-month recovery but that's what you need to do sometimes rather than try to struggle through when it affects every other part of your game as well.
"It's a bit of a blow for us and Ben but we decided it had to be done. It's the sensible thing to get him right for the back end of next year and the following year."