Del Bosque to test Spain's evolution in Brazil
Spain won an unprecedented treble of back-to-back European crowns either side of the 2010 World Cup and, as FIFA's top-ranked team, have probably been analysed more than any other side.
The only blemish on their recent record was a shock 2-0 defeat by United States in the semi-finals of the 2009 Confederations Cup in South Africa.
Maintaining their winning momentum, blending in new players with some tactical variations and perhaps most importantly, recovering the morale of a core group of players, will be a test for one of the game's most adept man-managers.
"We know that in football every one or two years things change and it is difficult to maintain this authority we have kept going since 2008," Del Bosque said in an interview with Diario de La Roja website.
"It is our obligation to keep trying."
Players from Real Madrid and Barcelona continue to form the backbone of the squad, with four and nine representatives respectively, but it has been a long and bruising season for both groups in physical and psychological terms.
Joining up with the avuncular Del Bosque and a relatively settled group of team-mates will be like a refuge from the turbulence of their club seasons and demoralising Champions League exits.
Goalkeeper Iker Casillas, Spain's unquestioned number one for more than a decade, has not played a competitive match since mid-January when he broke a finger in a match against Valencia.
Real's decision to bring in another keeper in Diego Lopez and a falling out with coach Jose Mourinho has meant the 32-year-old has watched from the bench during the season run-in.
Barca's Victor Valdes was outstanding as his replacement as Spain triumphed 1-0 in France to return to the top of their World Cup qualifying group in March, but he also has suffered a tough time after rejecting an offer of a contract extension at the Nou Camp.
Del Bosque, who prefers evolution to revolution, is likely to stay loyal to his captain, giving Casillas the chance to gain match practice in the warm up games against Haiti and Ireland.
Alvaro Arbeloa, Sergio Ramos, Xavi and Sergio Busquets have all been struggling with fitness problems, and influential midfielder Xabi Alonso has dropped out of the squad to have surgery on a groin problem.
Brazil could be the moment for Bayern Munich's Javi Martinez, 24, to step up into the midfield engine room, after a treble-winning season with the German side which included lifting the Champions League.
Martinez is one of a growing band of players based overseas, up from four at Euro 2012 to nine this time round, including eight who will be based in England from next season.
"More players are leaving to play abroad," Arsenal defender Nacho Monreal told a news conference in Miami, where the team were preparing to play Haiti.
"In Spain many teams are having a tough time. There are interesting offers abroad and we are leaving in search of new challenges."
Upfront, Del Bosque has to