Goalkeeper Sem Westerveld will be allowed to leave AZ on a free transfer in the summer. Several clubs are reportedly interested in the 23-year-old. OH Leuven from Belgium and the German club Kaiserslautern have been linked with him. Athletic Club has also shown interest. Westerveld, who played on loan at MVV this season, is eligible for the Spanish club because he was born in the Basque Country, which is consistent with their transfer policy.