Cameron McEvoy swam the third fastest time in history to storm to victory in the 100-metres freestyle at the Australian Championships with James Magnussen missing out qualifying in the event for the Rio Olympics on Monday.

McEvoy, the silver medallist in the sprint at last year's Kazan world championships, set a Commonwealth and Australian record time of 47.04 seconds to blitz his rivals in Adelaide.

McEvoy's time was just 0.13 secs outside the 2009 world record held by Brazilian Cesar Cielo (46.91secs).

Rising star Kyle Chalmers, 17, claimed the second qualifying place in the race for Rio in 48.03 secs, with London Olympics silver medallist Magnussen finishing fourth in 48.68secs.

It was a sensational time by McEvoy, 21, bettering Eamon Sullivan's Australian record by one-100ths of a second and the third-best time in the 100m freestyle event.

"I had some good words of advice leading into this race and it was pretty much was that a lot of the best swimmers in the world past and present get up behind the blocks and just put up the curtains on either side of the lane," McEvoy said.

"So I did that and I guess it paid off."

McEvoy, who was 17 when he went to his first Olympics in London, is now a strong gold medal contender for the event in Rio in August.

"I went to London and I was Kyle's age. It's going to be a different experience and I have just got to treat it like any other competition," he said.

"I shouldn't race it any differently, why fix something that's not broken.

"I have just got to go back and train my hardest and hope I can improve a little bit more."

- Magnussen 'shattered'-

Chalmers continued his dramatic improvement to take second placing ahead of James Roberts and Magnussen.

It was a shattered Magnussen, who was fighting back from a shoulder injury in his bid to go one place better than his silver medal in the event at the London Olympics in 2012.

"Tough race, I did everything I could physically to get back in shape," Magnussen said.

"Obviously, I'm pretty shattered but I have just got to go home, soak that in and get ready for the 50m freestyle tomorrow.

"Those guys just raced a better race tonight and I couldn't keep up with them and that's how strong Australian swimming is at the moment. It's going to be a cracking relay team for the Olympics."

Former world champion Cate Campbell posted a hot time of 52.41secs to qualify fastest for the women's 100m freestyle final in Monday's semi-finals.

It was Campbell's fastest time since she claimed the 2013 world title.

She finished ahead of reigning world champion and her youngster sister Bronte Campbell (52.78) who was second fastest ahead of Tuesday's final with Emma McKeon third fastest after winning the other semi-final in 52.98secs.

In Monday's other finals, Matthew Wilson (2:09.90) and Nicholas Schafer (2:10.75) finished in the top two places in the 200m breaststroke, but their times did not qualify them for Rio.

Madeline Groves (2:05.47) beat Brianna Throssell (2:06.58) in the women's 200m butterfly final.
Source: AFP