Untapered, unrested and unshaven to the point of sporting a beard, Australian Grant Hackett sent a loud, clear message to world swimming's middle distance king Ian Thorpe with a crushing World Cup 400m freestyle win in Melbourne.

Hackett, the world shortcourse record holder, was just over a second and a half outside his world mark, clocking 3:36.17 to beat American Chad Carvin (3:41.64).

But it was the manner of his victory - winning by five seconds over a quality field including world shortcourse bronze medallist Carvin and fellow Aussie Craig Stevens (3:46.29) - which signalled Hackett's intentions leading into next year's world championships in Barcelona.

After the race, Hackett said he was disappointed Thorpe had decided to skip the 400m.

Thorpe has bypassed all the middle distance events at this meet, deciding to only swim the 50m freestyle at the three-day shortcourse event.

"I want to show my rivals that I'm working hard and I'm coming here to race hard and show how fast I'm swimming," Hackett said.

"When I swim 3:36.1, win by five seconds, totally unshaved, unrested and untapered - I would have loved Ian to have been there. I'm sure it would have been a close race.

"I couldn't see him swimming any faster than 3:35 because he's in heavy work the same as I am so it would have been an interesting race."

Also missing Thorpe was his Sydney Olympics conqueror Pieter van den Hoogenband, who came close to breaking one of world swimming's longest standing world records.

Van den Hoogenband won the men's 100m freestyle final and was well under world record pace after the first 50m of the race.

But with Thorpe watching intently from the sidelines, the Dutchman tired at the end to post 47.20sec - less than half a second outside Russian Alex Popov's eight-year-old world shortcourse mark.

German Thomas Rupprath (23.49) also just missed a world mark, beating Aussie Matt Welsh (23.78) in the men's 50m backstroke in a time 0.26 sec outside the record he set earlier this week in China.

World 100m breaststroke record holder Emma Igelstrom gave her world mark a nudge, clocking 1:05.55 to beat Aussie Leisel Jones (1:05.91).

Igelstrom's swim was just 0.17sec outside her record.

Chinese 13-year-old Tianyi Zhang upstaged Aussie Jennifer Reilly in the women's 400m individual medley, swimming 4:35.69 to the West Australian's 4:36.37.

Other Australian winners were Elka Graham (54.42) in the women's 100m freestyle and Queenslander Robert Van Der Zant (55.45) in the men's 100m individual medley.

Russian Roman Sludnov (27.48) won the men's 50m breaststroke, while Swede Therese Alshammar (26.38) won the women's 50m butterfly.

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