She is 15, she is off to the Olympics and she has warned American superstar Natalie Coughlin that she is gunning for her.

Brisbane schoolgirl Emily Seebohm has no plans to be a shrinking violet in Beijing after sending a message to the world record holder at the Olympic trials.

"Natalie Coughlin I'm coming," she said.

Seebohm (59.59 seconds) continued her rise to the top of the pool by slicing another two tenths off her Commonwealth record in the 100m backstroke final.

She dropped her time by almost a second in the space of 24 hours as she continued to zero in on Coughlin's world mark of 59.21s.

Seebohm led home Sophie Edington (59.84s) as the records continued to tumble on the third night of action at Sydney's Olympic Park.

The Queenslander has enormous power in the pool for someone of such a tender age but she is still just a normal teenager at heart.

She forgot her swim suit before the finals and there was a mad panic in the build-up to her race.

But her head was still spinning and she felt guilty that her parents would have to fork out money to watch her go around in China.

"Mum said `no, we won't do it, we don't want to put pressure on you," Seebohm said.

"I was like `that is a good idea' because then I would not feel so bad if I could not make it but now I feel worse because they are going to rush to book flights and accommodation and it is really expensive."

Seebohm said that she was a little thrown by losing her 50m backstroke world record to Edington only a night after she had collected it.

"It was a big hit in the face for me," she said.

Breaststroke queen Leisel Jones (1:05.75s) maintained her stranglehold in the 100m before Beijing by keeping Tarnee White (1:06.46) at bay.

It was reunion of sorts as the pair represented Australia at the 2000 Sydney Olympics but Jones said she had plenty to do before the Beijing Games in China.

"I've still got so much work to do when I get back into training," she said.

Ash Delaney (53.68) put Australian backstroke back on the map by snatching Matt Welsh's national record as he and Hayden Stoeckel (53.86s) drove an arrow through Welsh's plans for a third straight Olympics.

"It has moved along so much," he said.

Nick D'Arcy (1:56.16) continued the assault by collecting the 200m butterfly national record in the semi-finals, taking one hundredth of a second off Justin Norris's mark.

Grant Hackett (1:47.03) showed his enormous versatility by touching out Kenrick Monk (1:47.10) in one of the races of the meet in the 200m freestyle final.

The distance master confirmed he would be stepping aside to hand Nic Sprenger the second individual spot in Beijing.

Hackett said the depth in the four-lap event augured well for Australia's plans to dethrone the United States in the 4x200m relay in Beijing.

"The States are the number one team but we are really starting to close that gap," he said.

Stephanie Rice (1:57.31) continued her blistering form in the pool, the 19-year-old following up her 400m individual medley world record on the opening night with the second fastest time by an Australian in the 200m freestyle.

But Rice will skip Tuesday night's final because she wants to focus her energies on the 200m IM, her plan being to put up a time for the 4x200m relay.

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