The mighty Germans were in for a rude shock as Belgium took the lead in the 30th minute through a field goal from Maxime Capelle to seize the initiative in the opening half. (Agencies)
The Belgians shocked the Germans once again when Arthur van Doren doubled the lead in the 45th minute through another field strike.
Germany livened up the match eight minutes from the hooter when Christopher Ruhr converted a penalty corner before Alexandre vn Linthoudt sealed the match in Belgium's favour with another field goal in the final minute of the game.
In the high-profile opening Pool B match, last edition's bronze medallist Australia spanked Pan-American champions Argentina 5-2.
Australia were by far the dominant side on display as they scored as many as five goals through Justin Douglas (7th), Frank Main (16th), captain Daniel Beale (23rd) and Casey Hammond (49th), while the other came from a penalty corner conversion by Jeremy Hayward (49th).
For Argentina, Joaquin Leonel Coelho (31st) scored through a field effort while captain Gonzalo Peillat converted a penalty corner in the 62nd minute.
Meanwhile in the opening match of the day, which turned out to be a high-scoring encounter, Korea thrashed Canada 7-4.
For Korea, Inwoo Seo (2nd, 16th, 37th) and Seungju You (7th, 31st, 42nd) slammed a hat-trick each, while the other came from the sticks of Minyoung You (49th).
For Canada, who produced a lacklustre performance in the opening half, Vikramjeet Sandhu (22nd), Gordon Johnston (52nd), Jannu Mahal (58th) and Oliver Scholfield (59th) were the goal-getters.
The mighty Germans were in for a rude shock as Belgium took the lead in the 30th minute through a field goal from Maxime Capelle to seize the initiative in the opening half.