Ajax centre-half Toby Alderweireld looks set to be sidelined for between two and four weeks with a hamstring injury. The 22-year-old Belgium international picked up the problem during Sunday\'s 1-1 draw at Eredivisie leaders AZ Alkmaar. The Dutch champions confirmed on their website that an MRI scan had showed a right hamstring strain, and that he would certainly be missing this weekend\'s game at Feyenoord. The 5 February encounter with FC Utrecht at the Amsterdam ArenA will also likely come too soon for Aldeweireld, but the club hope to have him available for the UEFA Europa League last-32 first leg against Manchester United on 16 February. Coach Frank de Boer will also be without Andre Ooijer, Kolbeinn Sigthorsson and Derk Boerrigter for Sunday\'s trip to De Kuip, with Netherlands right-back Gregory van der Wiel also doubtful due to a groin injury.