Barça has been looking for a versatile midfielder that could in an emergency also act as a defender. The idea behind the Song signing is to have a "back-up" player for Busquets &/or Mascherano. Barça has placed a 80M€ contract release clause on the player.
REAL MADRID player NURI SAHIN is still sounding as the replacement this season for Song. The Turk would go over to Arsenal as a loan.