Spain boss Vicente del Bosque has claimed that it made him "upset" to leave certain players out of his preliminary World Cup squad.
Napoli's Jose Callejon, Real Madrid's Alvaro Arbeloa and Isco and Barcelona's Marc Bartra were among those surprisingly left out of the travelling party for Brazil.
Del Bosque has admitted that it was difficult to leave certain individuals out, but said that it was "impossible" to hand every deserving player a place.
"Do you really think it hasn't upset me to have had to leave people out?" he told reporters at a press conference.
"It's impossible to put everyone on the list who deserves it. I won't give explanations about the players I didn't include, that would be a mistake.
"Callejon is one of the players we talked about. We always keep up to date with what he is doing, especially as Rafa Benitez is there. For us it is a daily thing."
Spain are the current European and world champions.
