Barcelona midfielder Ibrahim Afellay will be sidelined for at least six months due to a serious training injury on Thursday. Affelay, 25, tore the cruciate ligament in his left leg and will need to undergo surgery in the next few days. The operation will be performed by Ramon Cugat, the Catalan specialist usually chosen by Barca for knee operations on their players. The Dutch international joined Barca from PSV Eindoven in January 2011, but has enjoyed very little playing time under coach Pep Guardiola. The signing of Cesc Fabregas from Arsenal and the emergence of youngster Thiago had cast Affelay away from the lineup.