(Reuters) - Schoolboy pranks, over-inflated egos, a lack of team unity and unrealistic expectations filtered into the public domain on Thursday as reasons for Australia's poor showing in the Olympic swimming pool.

Australian swimmers suffered their worst Olympic performance for 20 years in London, failing to win an individual title and ending up with one relay gold, six silver and three bronze medals.

Swimming Australia announced a review into the disappointing display during the Games but are still framing the exact terms of reference and structure of the investigation.

Some individual team members, however, have already had their say on television, while the submission of one key figure, head coach Leigh Nugent, has been leaked to the media.

Many of the initial reports focus on the behavior of the men's 4x100 meters relay team, who, led off by 100 meters freestyle favorite James Magnussen, were expected to win gold but ended up out of the medals.

Tommaso D'Orsogna, who swam in the 4x100m heats, admitted to being party to misbehavior during a pre-Games camp in Manchester, where squad members made prank telephone calls and knocked on bedroom doors.

"People are kind of saying 'it's just boys being boys' but unfortunately I come back and I look back on that kind of thing and maybe that would be acceptable in schoolboy rugby... but this is the Australian Olympic team," he told Channel 10 TV.

"That kind of behavior shouldn't be tolerated nor should it be allowed.

"I can definitely confirm that there's no way that any other Australian team that went away to the Olympics would have been mucking around and doing that stuff."

UNREALISTIC EXPECTATIONS

Libby Trickett, who helped Australia to the women's 4x100m relay gold in her third Olympics, said the team spirit had not been the same as she had previously experienced.

"Obviously this is the first year I've been on the team since 2009, and I just felt in previous years there was a more cohesive unit," she told Fox TV.

Nugent's report to the Swimming Australia board, leaked to the Sydney Morning Herald, failed to mention any problems in the cohesion of the team and said he aimed to bring some perspective to the debate.

"It appears evident following the barrage of criticism the expectation placed on this team was based on the fantasy that the result from four years prior will automatically repeat itself regardless of the comparative world positioning," he wrote, according to the leaked document.

"Our process is to evaluate objectively and to continue to improve from the low base we started from in 2009 and establish a higher platform to launch from in 2013. This is a time where we all need to pull together, not fall apart."

D'Orsogna, meanwhile, also said he had witnessed favoritism for some of the bigger names in the team.

"It is a little bit disappointing to see and I think it is part of the reason why the results in London weren't what we had expected with people maybe putting themselves up a little bit higher than the rest of the team," he said.

As for the allegation that team members had been subjected to initiation rituals involving Stilnox - a strong sedative banned by the Australian Olympic Committee just before the Games - D'Orsogna preferred not to comment.

"I'm not going to be that guy that lies on media," he said. "I'm not going to be the guy that stands up here and lies to Australia but at the same time I'm just not going to comment."