Vicente Del Bosque wants Sergio Busquets and Jordi Alba to prove their fitness ahead of the World Cup, reports in Spain claim.
AS says that there are concerns over the Barcelona pair after Busquets suffered a pelvic injury against Atletico Madrid in the last League game of the season and Alba missed much of the final months of the campaign with a thigh injury.
Both are expected to be involved in Friday’s friendly against Bolivia.
Jesus Navas is also a doubt, with the Manchester City winger not playing since April 13 due to an ankle injury.
There is a chance Navas could be left out of the 23-man squad to go to Brazil as a result.
Gerard Deulofeu was called into the squad to play Bolivia as cover with the ex-Sevilla man not yet ready.
A further problem arose with Cesc Fabregas, who needed treatment on his ankle after an incident in training but was able to resume practice.
There were no clues as to the starting XI to play Bolivia from training, AS add, but it’s expected Cesar Azpilicueta will play, as will Gerard Pique and Raul Albiol.
Ander Iturrapse could line-up in midfield behind an attack containing Pedro, Juan Mata, David Silva and Fernando Torres.