Lee Troop won a third national 10,000m title at the Australian Olympic track and field trials but would not be budged from his twin goals for 2004.

Troop wants to smash Robert de Castella's 18-year-old national marathon record of 2 hours seven minutes and 51 seconds in London in April.

Then he will gun to become only the fifth Australian to record a top-10 finish in an Olympic marathon, so the Athens 10,000m is out of the equation.

"I've changed my focus completely, I've just been training so hard for the marathon," said the 30-year-old Victorian.

"I feel strong and I feel confident that I'm in better shape than I've ever been, so that augurs well going in for London.

"The only things I care about this year is top 10 at Athens and breaking Deek's record in London."

Troop defied cold, wet and blustery conditions at Sydney Olympic Park with a solid display of front-running to win the 10,000m in 28:32.43, ahead of Andrew Letherby and Brett Cartwright.

"I felt terrible throughout the run, then after about 10 laps I got a stitch and I found it hard to shake but I just kept pushing it," said Troop.

In the only other final on day one of the four-day trials, Queenslander Peter Nowill won a fourth successive 3,000m steeplechase national title in 8:33.23.

Former boxer John Steffensen pulled no punches in throwing down the challenge to the big names after qualifying fastest for the 400m final.

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