Vezina, a distant relative of the Canadian ice hockey legend Georges Vezina, tested positive for three substances , including pseudo-ephedrine and an anabolic steriod. Canada beat the United States 7-6 on Tuesday for the gold medal. Yesterday's announcement means that the US is awarded the gold, Argentina silver and Brazil the bronze.
The revelation came on a day of double victory for Cuba, who emerged victorious both on the baseball field and in the political arena.
On the baseball field, the Olympic champions maintained their goal of reaching the 2000 Games with a 3-1 victory over the Dominican Republic. They were due to face the undefeated Canadians in a semi-final last night, with the winners assured of a place at Sydney.
Cuba also received support off the field when the 41 other participating countries joined them in a statement deploring the treatment of Cuban athletes and officials by some journalists and sports agents.
Cuban officials have complained that scouts have been trying to lure their athletes away by offering lucrative contracts and that local media sources have dwelt too much on the topic of player desertions.
The Cubans were further angered by press allegations that their baseball team had deliberately lost a qualifying match last week to avoid being in the United States' half of the draw for the knockout stages.
"These negative actions have affected not only Cuba, but all of the Americas and have interfered with the Olympic movement and the spirit of equality and good sportsmanship," the statement said.
In tennis, the United States' Wimbledon semi-finalist, Alex-andra Stevenson, advanced to the quarter-finals, beating Fran-cine Harvey of Antigua, 6-0, 6-0.
The US extended their runaway lead in the overall medals table after picking up seven more golds on Saturday.