The man who scored Argentina's first goal of the tournament in the win over Nigeria was born to a German father, who passed away in 2004, and an Italian mother. He also holds German and Italian passports.
But where football is concerned it is the albiceleste who count and now the Marseille central defender is plotting the downfall of the land of his forefathers.
The 32-year-old who started out with Newells Old Boys before spells with the likes of Paris Saint Germain and Manchester United has not always been flavour of the month with the fans. There have been online campaigns to have him dropped, but coach Diego Maradona is a fan and that is what counts.
Regarding the goal which set Argentina on their winning way, Heinze remarked modestly that "this is what happens in football - I was in the right place at the right time."
He may not have the global cachet of Lionel Messi, yet Heinze is the linchpin of a defence which has held up well so far despite being perceived as a relative weakpoint.
Heinze can trace his roots to a family of Volga Germans who settled in the Argentine province of Entre Rios north of Buenos Aires. Whereas Maradona's squad contains several players of Italian origin Heinze is the only one with German ancestry. In the late 18th Century, many Volga German families left their far-flung corner of Russia and crossed the Atlantic.
Heinze has earned numerous domestic honours since starting out with Newells in 1997. He had a year at Real Valladolid in Spain but really came to prominence - and to the attention of Sir Alex Ferguson - at Paris Saint Germain from 2001 and that led to a move to Old Trafford in 2004.
But three years later and after a Premier League title win, he switched to Real Madrid, where he added a La Liga crown in 2008 before a 2009 move to Marseille, where he has just lifted another domestic championship.
Now Argentina will hope that at least their 'German' will be celebrating come Saturday night four years on from Argentina's penalty shootout loss to the same opposition at the same stage in Berlin.
If the South Americans are to win the duel against a young and energetic German side, Heinze and defensive colleagues Nicolas Otamendi, Martin Demichelis and Nicolas Burdisso will have to hold the line while hoping Messi and company can produce the goods at the other end.