The sight of Germany sweeping Australia aside 4-0 in their opening game at the FIFA World Cup came as a surprise to some. With injuries depriving coach Joachim Löw of key figures, the young side he selected was considered something of an unknown quantity, but the confident, free-flowing attacking display they produced soon dispelled doubts about Germany's potential.
For a significant percentage of that team, winning 4-0 in tournament play is nothing new. Manuel Neuer, Mesut Özil, Sami Khedira and substitute Marko Marin all impressed against Australia less than a year after leading Germany to a 4-0 triumph over England in the final of the 2009 UEFA European Under-21 Championship.
Özil was named man of the match in that victory and sparkled again against Australia, while Kadira, captain of that U21 side, made light of the absence of Michael Ballack in the centre of midfield. Neuer was making just his sixth senior appearance, but keeping clean sheets in tournament play has come to be expected of him; he only conceded once in Germany's five matches in Sweden last year.
In all, six members of Germany's 2009 U21 Championship-winning selection have stepped up to the World Cup squad, with new Manchester City FC signing Jérôme Boateng and Hamburger SV's Dennis Aogo also involved. If Germany's trust in their 2009 U21 vintage is most pronounced, they are not the only team to be reaping the benefit of last summer's tournament.
For England, James Milner, who enjoyed a breakthrough season at club level, started their Group C opener against the United States, and goalkeeper Joe Hart, England's hero in the 2009 semi-final shoot-out victory against Sweden, is also in the squad.
The other three sides at the World Cup that also competed in the 2009 U21 finals, Italy, Serbia and Spain, also boast graduates from last summer's tournament. Italy, defeated by Germany in the semi-finals, include Domenico Criscito, Claudio Marchisio and Salvatore Bocchetti; Gojko Kačar, Zoran Tošić and Ivan Obradović are in the Serbia squad while Javi Martínez has made the grade for Spain.
It is not only the 2009 U21 generation represented in South Africa. Europe's 12 competing nations boast rising stars who have also been involved in qualifying for the 2011 UEFA European U21 Championship in Denmark.
Germany's U21s have in some respects been a victim of their own success. Thomas Müller, a scorer against Australia, Holger Badstuber and Toni Kroos were all promoted to the senior team during the course of U21 qualifying before being included in the World Cup squad. As a consequence Germany have at times been depleted at U21 level and that has been reflected in their results in Group 5, where they trail the Czech Republic by five points.
Elsewhere, Sotiris Ninis scored a crucial equaliser for Group 9 leaders Greece in a draw against England in September and is now helping his side on the world stage; Eren Derdiyok, also a scorer in U21 qualifying for Switzerland, is proving key figure in Ottmar Hitzfeld's plans in South Africa, while Miroslav Stoch and Vladimír Weiss have featured prominently for Slovakia.
The priority for most U21 players, however, remains qualification for the Denmark next year and with the likes of Stevan Jovetić (Montenegro), Romelu Lukaku (Belgium), Mario Balotelli (Italy) and Aaron Ramsey (Wales) among those currently making a name for themselves on the U21 stage, the next generation is preparing to take the step up.
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