• Wales midfielder has played with injury since October
• Allen substituted at half-time of defeat by Southampton
Joe Allen is scheduled to have surgery this week on a shoulder injury that will sideline the Liverpool and Wales midfielder for the rest of the season.
The 23-year-old suffered a recurrence of the problem in October but played on for Brendan Rodgers's team to delay an anticipated lay-off of three months.
The injury has deteriorated, however, and Allen was clearly in discomfort during Liverpool's 3-1 Premier League defeat at Southampton on Saturday. He was substituted at half-time and it has been decided to operate this week in order for the £15m signing from Swansea City to be fit for the start of pre-season training.
Allen's condition has also forced him to withdraw from the Wales squad for the World Cup qualifying double-header against Scotland at Hampden Park on Friday and Croatia at Swansea's Liberty Stadium next Tuesday.