The Roja boss insists there are plenty of players in with a chance of making his squad for next summer's finals and warned his side not to underestimate Chile
The 62-year-old has a wealth of talent has his disposal, but insists any player with designs on the Roja team will be given the duration of the 2013-14 season to impress him prior to next summer's finals.
"We have a fixed group of players, a big squad with players that have done a lot for the team and will continue to do so," he told reporters.
"But we won’t close the door to anyone."
With World Cup qualification all but secured following Friday's 2-0 win over Finland, Spain face Chile in a friendly clash on Tuesday - although Del Bosque has warned his side not to allow their level to drop against the South Americans.
"We are going to use the occasion to allow everyone to participate and use the game as preparation for the matches with Belarus and Georgia next month," he said.
"If we don’t take Chile seriously we will suffer, because they compete to the highest level and are always looking to attack. They have always been a very physical side when we’ve played them."
Spain will likely have to make do without the services of David Silva for the game, as the Manchester City playmaker is nursing a groin problem.
"He joined the squad with a knock to the thigh that he had while playing for Manchester City," Del Bosque explained.
"Yesterday he completed training fine but then felt some pain and it seems like he has a slight groin strain. But he wanted to travel with us."