Steve Harper could need surgery to address a knee problem. The 36-year-old missed Tuesday night's 0-0 draw with Manchester United and has now been ruled out of Saturday's trip to Blackpool. Alan Pardew: "Harps isn't right and we will have to review him over the next couple of weeks. "He's not necessarily out for the season, but it could be that he needs a small operation just to sort his little problem out. "It's not a major problem, but we will have a look at that and weigh that up over the next couple of weeks."