International Olympic Committee boss Jacques Rogge has condemned betting on the naming of Australia's flag bearer after controversy over an apparently well-informed plunge.
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Basketball superstar Lauren Jackson, who was named as flag bearer by Australian chef de mission Nick Green at a team function on Thursday night, had opened at 30-1 in betting and was backed into 1-2 odds-on before bookmakers stopped taking bets on the outcome.
Green played down talk of an investigation by the Australian Olympic Committee into how the information may have got out and said only a few people within his organisation knew about the choice.
But Rogge was not happy about the situation on the eve of the Games.
"Match fixing is what we really want to stop, so in this situation the letter of the law is not broken," Rogge told reporters on Friday.
"But you should not bet on it.
"It has nothing to do with manipulation of the result but I feel unease with this event."
Green said he was disappointed with events that led to the plunge on Jackson, 31, a three-time WNBA Most Valuable Player with Seattle Storm.
"We saw it like everyone else yesterday and we're disappointed with it, maybe there's an assumption that it might have leaked through social media," Green said.
"We have a very strict policy on betting within our team. There's been a lot of speculation on Lauren but ultimately Lauren is absolutely the most amazing choice for the flag-bearer and I'm honoured to make this decision."
When asked about comments from diver Matthew Mitcham that Green may not have been as discreet as he could have been when calling Jackson in to tell her of the flag bearer appointment four days ago, Green said as far as he was concerned few people knew what was happening but others may have made an assumption.
"The people who knew, I could count them on a couple of fingers. It was a very small group," he said.
The popular Jackson is competing at her fourth Olympics and becomes the second basketballer to receive the honour of carrying the Australian flag at an Olympics following Andrew Gaze at the 2000 Sydney Games.
Meanwhile at least one UK bookmaker stopped taking bets on Sir Roger Bannister, the first man to break the four-minute mile, to be the person to light the Olympic cauldron at the opening ceremony of the Games.