In a chat with Marca website the World Cup winning coach said: "We've had 13 training sessions and two friendlies and things are looking good.
"We're sticking to our usual formula and are optimistic ahead of the beginning of the tournament."
Diego Costa and Juanfran, who were struggling with fitness, looked good in the friendly against El Salvador and the coach was happy with the positive news.
"Juanfran played well and didn't feel any pain, which is good news, and the same goes for Costa.
“He showed flashes of what he can do; he faded, but he hadn't played for a long time, so we wanted to keep him out there for as long as possible. He's ready for the World Cup."
Del Bosque said that there was no issue with the fitness of Jordi Alba as the fullback was only struggling with blisters.