World record holder Asafa Powell's first competitive strides on the long road to Beijing could hardly have been more impressive.

The Jamaican sprint superstar defied the pain of a cut knee to storm to victory in the 100m at the Melbourne Track Classic in a sizzling 10.04 seconds.

Powell, 25, only made the decision to run after completing a long warm-up, satisfying himself and coach Steve Francis that the knee injury had healed sufficiently.

And if there were any nerves, they were gone within 20 metres of the start by which stage he had the field at his mercy.

Fellow Jamaican Michael Frater trailed home a distant second in 10.25 and Australian Matt Shirvington was third in 10.35.

"I'm very surprised because I haven't done anything for two weeks and tonight's the first time in spikes since then - it was way faster than I thought," said Powell.

It was a remarkable first-up effort by the big Jamaican, with his winning time only one-hundredth of a second slower than the 10.03 he ran to claim the Commonwealth title two years ago in Melbourne.

Powell also broke the 10-year-old meet record of 10.06 set by former Olympic and world champion Maurice Greene of the United States.

His likely match-up with reigning 100m world champion Tyson Gay - who had his measure last year in Osaka - shapes as one of the most anticipated events of the Beijing Olympics.

"It's very important (running here) for my training," said Powell.

"I came to Australia to train and race and my training wouldn't be complete if I didn't run here.

"It proves I'm way faster than 2006. I haven't done anything in two weeks - 10.04 is very impressive.

"This year I'm way, way stronger than the last few years.

"I've just got to stay on the track."

Powell's remarkable run was one of several standout performances on a great night for the sport in front of a large crowd at Olympic Park.

Olympic and world champion Jeremy Wariner from the United States won the 400m in 44.82, Scott Martin smashed the Australian shot put record with a huge heave of 21.27 metres and Craig Mottram powered away in the final 250 metres of the 5,000m to win the national title in 13:11.99.

Wariner had been under the weather since arriving in Australia and needed medical assistance after suffering dehydration following the race.

But on the track he was untouchable, leaving Australians Clinton Hill (45.78) and Sean Wroe (45.88) to fight out the minor placings.

"I had a great race today, I got to see where I was in my training and now I go back and rest for a couple of days and then get back on the grind," said Wariner.

"This is a really fast start for me this early in February."

Martin dominated the shot put, with his best effort of 21.27m obliterating the five-year-old national record of 20.96m set five years ago by Queenslander Justin Anlezark.

Martin, 25, has to limit his training because of an ongoing foot injury.

But he was feeling no pain tonight after obliterating his previous personal best of 20.63m set earlier this year.

Ethiopian Abreham Feleke did much of the front-running in the 5,000m, before being overwhelmed by Mottram and Kenyan Shadrack Kosgei in the final lap.

Mottram has been pre-selected for this event at the 2008 Olympics.

Other Australians to better the Olympic A qualifying standard tonight included Donna MacFarlane in the women's steeplechase, Lachlan Renshaw in the 800m and Tamsyn Lewis in the 400m.

It was Mottram's sixth national 5,000m title.

Mottram's time was the second best 5,000m he has ever clocked in Australia - after his 12:58.19 for silver at the 2006 Commonwealth Games in Melbourne.

And the 27-year-old said the fact he had run the time when not entirely at his peak gave him confidence at the start of a busy Olympic year.

"I wasn't feeling quite as 100 per cent as I should be - I'm as strong as I've ever been but not as smooth as I can be," Mottram said.

"That's the quickest apart from the Commonwealth Games I've ever run in Australia. That's what you get when you get world-class athletes out here - you run fast."

The tactical nature of the race also pleased Mottram, who can look forward to a year of similar sparring with world-class Africans at both the world indoor titles next month and the Olympics in August.

With a Kenyan pacemaker and another Kenyan, Ethiopians and Tanzanians surrounding Mottram for most of the race, Mottram kept churning out the laps knowing he would have enough in reserve as the majority of his rivals dropped away.

"You've got to stay calm and realise that even though there's seven athletes with you, there's not necessarily going to be seven at the bell lap," he said.

"I felt calm and relaxed. With three laps to go I was working pretty solidly, but it's been a long time since I've been dropped in a 5k and it wasn't going to happen tonight."

After bemoaning the lack of competition to push her last week, Tamsyn Lewis ran an Australian A qualifier in the women's 400m tonight.

Lewis, who is aiming at the 800m in Beijing, clocked 51.55 seconds to beat Jamaican speedster Sherone Simpson.

The 29-year-old Victorian powered through her third 100m to head her Jamaican rival, then did enough late to hold her off.

"I've been struggling all year in the 400 to get that time because there hadn't been the competition. Well, I had the comp tonight," Lewis said.

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