Spain won the World Cup for the first time in South Africa in 2010 and in June and July will attempt to become the third nation to retain the trophy after Brazil in 1962 and Italy in 1938.
Coach Vicente del Bosque is due on Friday to announce his squad for Wednesday's friendly against Italy in Madrid, providing an indication of who is likely to be in his 23-man party for the finals in Brazil.
The 32 World Cup teams are obliged to send their squad lists to soccer's ruling body FIFA by June 2. The opening game is between the hosts and Croatia 10 days later.
Spain are in Group B with Netherlands, the side they beat in the 2010 final, Chile and Australia.
Bolivia failed to qualify for the World Cup.
(Reporting by Iain Rogers; editing by Tony Jimenez)
