Alex Walmsley is set for a lengthy spell on the sidelines after fracturing a bone in his neck.
The England star sustained the injury in the club’s win over Warrington earlier this month and scans have confirmed that he is set to miss a significant period of the season.
It comes as a huge blow to Saints, who suffered their first defeat of the season against Leeds last week without their star forward.
The 27-year-old underwent an operation and surgeons have confirmed he will make a full recovery.
Walmsley enjoyed a superb 2017 season, finishing the year as Super League’s top metre maker and earning his first appearance for England, going on to feature in the World Cup Final.
“It is obviously a massive blow to our team given the fact that Alex is the best front rower in Super League,” head coach Justin Holbrook said.
“He has been in great form already this year after a good World Cup. But importantly, the news that Alex will make a full recovery from the injury is one we all welcome.
“Alex has had an operation to correct the damage and will now begin his recovery led by our medical team. We all wish him well.
“The surgeon has told both Alex and the Club that he will make a full recovery and his neck will be stronger than ever.”