Portsmouth have suffered a fresh blow to their stuttering start to the season with the news that Harry Redknapp is set to be without Niko Kranjcar after the midfielder underwent an operation on ruptured ankle ligament. Kranjcar picked up the injury while on international duty for Croatia against Slovenia last week and is expected to be on the sidelines for up to three months. A statement on the club's website read: 'The operation took place at the Hampshire Clinic in Basingstoke and was performed by James Calder, a consultant orthopaedic surgeon specialist in foot and ankle surgery. 'The same surgeon operated on former Pompey player Pedro Mendes last season when he had a similar injury. 'Blues club doctor, Nigel Sellars, attended the operation along with the orthopaedic surgeon to the Croatia national team. 'The 24-year-old will wear a non-weight bearing case for the three weeks before beginning rehabilitation weeks. 'He faces an estimated eight-to-12 weeks before being able to play first-team football again.'