Australia's men's water polo team paid the price for Olympic-sized jitters in their three-goal loss to world champions Italy, coach John Fox says.

Three-time Olympic champions Italy logged an 8-5 victory over the Australians in their opening preliminary group match of the London Games.

Italy streaked to a 3-0 break by quarter-time and Fox said his players were overawed by the occasion.

"You can talk about anxiety and nerves and the pressure of playing at the Olympics - hopefully it is out of our system," Fox said.

"It was pretty obvious that Italy were more prepared than we were at the start.

"You can't give the world champions a three goal start.

"The rest of the game was even, if not we were ahead."

But the final margin perhaps flattered the Sharks, who netted two late goals to add some respectability to the scoreline.

Australians Richie Campbell, Tim Cleland, Rhys Howden, Aidan Roach and Johnno Cotterill all scored in their tournament opener at Water Polo Arena.

But the Sharks were repeatedly denied by a tight Italian defence headed by captain Stefano Tempesti.

"Tempesti is the best goalkeeper in the world, without a question," Fox said.

"He had a good game today and is the key to their defence, when he is playing well they are very hard to penetrate."

Australia play Kazakhstan on Tuesday in the second of five preliminary matches, with coach Fox remaining confident of advancing to the quarter-finals.

"The boys are positive in themselves," Fox said.

"We have got Kazakhstan in two days, so if we get a win on the board then we're back amongst it."

NZ Newswire