Argentina stunned medal favorites France with a straight-sets win on the opening day of the men's volleyball competition on Sunday.
Jorge Elgueta, impressive at the net with six from 11 spikes, spearheaded the upset of the world number four side by the world number eight.
Philippe Bara Cysique was the highest scorer for France with 15 points.
Elsewhere, Poland beat Serbia-Montenegro 3-0, Holland edged Russia 3-2 and Brazil beat Australia 3-1.
Argentina had trailed France 23-22 in the first set but rallied after two kill-blocks and a spike from Gaston Giani.
And in the 48-point third set, Argentina were aggressive at the net to clinch the set and the match.
After the win Elgueta said: "It was just a great match for us.
"There are many matches ahead, but we have thoughts and hopes."
Meanwhile, French captain Dominique Daquin insisted his team had not underestimated the South Americans.
"All the teams in this pool are very aggressive," he said.