THERE is no doubt Grant Hackett's world record swim in Melbourne yesterday will send a minor shudder through his Olympic rivals, but Australian head coach Alan Thompson believes the message it sends to Hackett is far more significant.

Just three weeks out from the Games, Hackett, swimming at the Victorian shortcourse championships at the Melbourne Sports and Aquatic Centre, produced a stunning 800 metres swim, clocking seven minutes 23.42 seconds, slicing 1.86 seconds off the world record he set in Perth in August 2001. Describing his swim to Channel Seven, Hackett said: "I just put my head down and just went for it. It's pretty exciting."

What makes the swim even more impressive was that it came at the end of a week of very heavy training and before he begins his taper for Beijing.

Only 24 hours earlier Hackett had signalled the type of form he was in by producing a 3:35.16 effort in the 400 metres freestyle, a time which was just 0.58 seconds outside the world record of 3:34.58 he set in Sydney, on July 18, 2002.

"I don't think it's about what it says to the rest of the world, because I don't know if he's doing it for anyone else other than himself," Thompson said. "But I think what it will do is give him good confidence going into the race preparation phase … he would be feeling pretty confident now I think, and that's always a good thing for a swimmer."

Hackett's coach Ian Pope said after the times were not actually unexpected as both marks had been targeted heading into the weekend.

"We knew he'd be right on the mark," Pope said. "Our intentions were to go that fast this weekend.

"We knew what we had done in training and every race he's done all the way along in this preparation has been fast. He did a 7:48 (800 metres long course) a couple of weeks ago at a low-key meet here, he did well at the grand prix (in Sydney) and he's just raced fast all the way through. The way he swam these races, he finished them with very fast speed. He came home in a 53 seconds (for the final 100 metres), he went out in 3:41 (first 400 metres), came back in 3:42 (second 400).

"The way he did it was very impressive and will certainly build his confidence. He's in hard training, he's tired and it certainly was very good leading into the Olympics."

Hackett, Pope and two Olympic team members, Travis Nederpelt and Matt Targett, left last night for a week long camp in Singapore.