Vicente del Bosque's principle concern going into next year's World Cup is that his players might have lost the humility that underpinned recent success, the Spain coach was quoted as saying on Tuesday.
Del Bosque led Spain to their first World Cup triumph in South Africa in 2010 and two years later they went on to defend the European crown they won under Luis Aragones in 2008.
A number of players still active for the national team featured in all three competitions, including captain and goal-keeper Iker Casillas, midfielders Xavi, Andres Iniesta, Xabi Alonso and Cesc Fabregas and central defender Sergio Ramos.
Del Bosque said in an interview with As newspaper that it was crucial that the players did not let past successes go to their heads at the event in Brazil starting in June.
"They are players who have won a great deal, almost everything, and they see things through different eyes compared with five or six years ago," Del Bosque said.
"It is fundamental to be humble, sporting and good lads, nice guys.
"We have to forget about the past and not revel in what we won in the years before.
"We are going to another World Cup, a different one, in a different country and on a different continent, and we have to
go there with the same spirit as in South Africa.
Spain begin the defence of their title against Group B rivals Netherlands, the team they beat 1-0 in the final in 2010, in Salvador on June 13.
They play Chile in Rio De Janeiro on June 18 and Australia in Curitiba five days later.
"Spain has a good national team and is not inferior to anyone but we must be cautious.
"We are the team to beat and there are powerful opponents, mainly the South Americans including Brazil, Colombia, Argentina and Chile.
"It is not easy and we have to show respect for all our opponents."