Ian Thorpe washed away days of disappointment with one swim by setting a stunning Commonwealth record in the 200m individual medley at the Australian championships in Sydney.

Thorpe clocked 2m00.11s to slice 0.15s off Matt Dunn's 1998 mark of 2:00.26 and record a time that would have won him bronze at the Sydney Olympics and silver at the 1991 world championships in Fukuoka, Japan.

He trounced Commonwealth champion Justin Norris (2:01.19) to record the fifth fastest time internationally of the past year.

Until the medley, Thorpe had failed to find the form that has taken him to 17 world freestyle records.

Swimming at his first nationals with new coach Tracey Menzies by his side, Thorpe has won predictable gold medals in the 100, 200 and 400m freestyle but his times have been way off his best.

"Doing one race really well at the end of the meet, it kind of cancels out a little bit of the disappointment," he said after the medley.

"It was a good swim. I was happy with that. I'm pleased with where I'm at. I would have loved to have gone under two minutes. That was my ultimate goal and I was just off that. I'm looking forward to doing a few more of them."

Until Thursday night, the spotlight during the championships had been on his new partnership with Menzies rather than his swimming.

But his medley result is expected to go a long way towards silencing any critics of his split from childhood mentor Doug Frost six months ago.

The swim has also revived the possibility of Thorpe next year emulating Mark Spitz's 1972 feat of seven gold medals at a single Olympics.

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