Super League leaders St Helens will be without full-back Jonny Lomax for the remainder of the season.
The 23-year-old suffered a knee injury in the second half of Saints' 42-0 defeat by Catalan Dragons on Saturday and requires an operation.
"This is obviously a blow to the team but more importantly to Jonny," coach Nathan Brown told the club website.
"Jonny has a strong character and we're sure he will come back and prove once again to be a pivotal player for us."
Lomax had been used in various positions during the early stages of his career with Saints but has settled into the full-back role since Brown took charge of the club at the start of the 2013 season.
His impressive form was enough to earn a call-up to the England squad, although he has been forced to miss their mid-season training camp in Loughborough and is unlikely to feature in the Four Nations tournament later this year.