MADRID (AP) -- Vicente del Bosque's calm, composed and assured demeanor doesn't quite reveal the true extent of the stress he has endured in leading Spain to World Cup and European Championship titles.
Spain will be heading to Brazil looking to become the first country to repeat as champion since 1962, and the first European team to win the World Cup in South America.
Don't expect Del Bosque to show signs of cracking, even if it's bubbling within.
''I'm happy with what I do, my work,'' Del Bosque said, ''but it's true that there are moments in which I'm a nervous wreck.''
Del Bosque is Spain's most successful coach with more victories than any other. Under him, Spain won its first World Cup in South Africa four years ago and then defended its European Championship title in Poland and Ukraine in 2012.
Both events were marked by slow starts - and strained nerves. Spain opened the 2010 World Cup with a loss to Switzerland, and started Euro 2012 with a 1-1 draw against Italy.
''I remember when (Antonio) Di Natale scored against us in the Euro, I wasn't expecting that and I was suddenly overwhelmed with perspiration,'' Del Bosque said. ''But then Cesc (Fabregas) scored and that stopped it.
''When you don't win you suffer a lot, I'll get a headache. And when we lose, it hurts tremendously.''
Luckily, Del Bosque hasn't had to suffer much since replacing Luis Aragones following Euro 2008. Spain has lost only eight times in 84 matches under Del Bosque, and only three of them were in competitive matches.
''Our past achievements offer no guarantee of future triumphs,'' said Del Bosque, who looked slightly rattled when Spain was drawn to open Group B against the Netherlands on June 13 in a rematch of the 2010 final. ''My message is to stay humble, be vigilant, and not to let us believe that anything will be easy at the World Cup.''
The 63-year-old Del Bosque's job may look easy on paper, but the former Real Madrid coach's astute ability to manage egos, talent and never waiver from his diplomatic approach has proven valuable.
Del Bosque has tinkered just enough with his teams through the years to maintain Spain's superiority. And this time around, it's no different.
Del Bosque is expected to bring Brazilian-born striker Diego Costa to the event, which means Fernando Torres is likely to be omitted from a major tournament for the first time in 10 years. Midfielder Juan Mata's place is also under scrutiny with talents such as Thiago Alcantara of Bayern Munich and Isco of Real Madrid ready to step in.
Perhaps his brashest move has been to stick with Iker Casillas in goal, despite his captain being relegated to a backup role with Real Madrid.
''We've already touched on Casillas' case and he plays in the Champions League and the Copa del Rey, so if he was so bad I imagine his coach would not play him in such important matches,'' Del Bosque said. ''Casillas is not only a player with a brilliant past but is a player with a present impact.''
Despite fractious and often strained club rivalries involving his players from Barcelona and Madrid, that all dissolves when Spain gathers to play. And Del Bosque's calm - on the surface, at least - has been key to that cohesion.
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