Substitute Masashi Oguro scored with 14 minutes left to give Japan a 1-0 win over Greece on Sunday and keep the Asian champions in the hunt for a semi-final place at the Confederations Cup.
Japan had looked set to pay a high price for their bad finishing, with strikers Atsushi Yanagisawa and Keiji Tamada guilty of a series of appalling misses in a one-sided game.
But Zico's team showed patience as well as masterly technique and they took the lead when Oguro ran on to a pass from Shunsuke Nakamura and tucked the ball past Antonis Nikopolidis.
Angelos Haristeas brought one good save from keeper Yoshikatsu Kawaguchi with six minutes to go but otherwise Japan were untroubled by a disappointing Greece display.
Victory gives Japan three points from two matches, while Greece are left without points.
Brazil and Mexico, with three points each, were due to meet in the late game in Group B in Hanover.