The United States on their way to victory over Australia ©Getty Images

The United States are the early leaders after the opening day of the International Volleyball Federation (FIVB) Men's World Cup in Japan.

They claimed a 3-0 straight sets win over Australia, triumphing 25-23, 25-12, 25-15 at the Green Arena in Hiroshima to go top of the sole 12 team group.

Poland are second after easing past Tunisia in Hamamatsu with a 25-17, 25-15, 25-20 straight sets success.

Elsewhere, there were also victories in Hiroshima for Italy and hosts Japan who saw off Canada and Egypt respectively.

The Italians opened up a 2-0 lead against the Canadians after taking the opening sets 25-19, 25-20.

Canada got themselves back into the match by taking set three 25-22, but Italy were not to be denied as they closed out the match with a crushing 25-13 win in set four.

Italy were too strong for Canada on day one
Italy were too strong for Canada on day one ©Getty Images

Japan, meanwhile, needed five sets to see off Egypt and leave the home crowd happy.

In a topsy-turvy encounter, the Japanese took the first set 25-19 before Egypt levelled the contest, shading the second 25-23.

The hosts moved back in front with a 25-18 win in set three but Egypt struck straight back again by taking the fourth 25-17.

In the fifth, it was Japan who held their nerve to win the decider 15-7.

Two further games in Hamamatsu saw Russia beat Venezuela in straight sets, 29-27, 25-16, 25-15, while Argentina came past Iran in four, 25-27, 25-22, 25-22, 26-24.

Japan is due to host more games tomorrow as the race for World Cup glory continues.

In Hiroshima, Australia face Italy and Egypt face Canada, while hosts Japan will play the United States.

The Japan versus US game will no doubt be a poignant occasion for some, with Hiroshima being one of two cities targeted with an atomic bomb by American forces during the Second World War.

Hamamatsu will host games between Venezuela and Argentina, Tunisia and Iran and Poland and Russia.

The top two teams in the tournament will qualify for next summer's Olympics in Rio.

Japan has just finished hosting the World Women's Championships, which were won by China.

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