Five-time Olympic gold medallist Ian Thorpe's comeback again stalled when he failed to qualify for the 100m freestyle final in his first competitive swim in Australia since 2006.

Thorpe, 29, announced a return to action in February last year following his retirement in November 2006 after winning five Olympic gold medals and 11 world titles.

But it has been a rocky road since then with his modest times a shadow of his former self, throwing into doubt his ability to qualify for the London Olympics with the Australian trials fast-approaching in March.

It failed to get any better at the Victorian state swimming championships where he finished seventh in his heat to miss Friday night's 10-man final at the Melbourne Sports and Aquatic Centre.

Thorpe swam the 13th quickest time of 51.05 seconds, well behind fastest qualifier Matt Targett who clocked 48.86.

Another Olympic champion on the comeback trail, Michael Klim, qualified seventh for the final with a time of 50.15.

A sluggish Thorpe turned last at 50m and could only make up one place on the way home, recording a slower time than the 50.84 he swam in Italy last month and a long way from his best of 48.56, swum in 2004.

Thorpe will also contest the 200m in Melbourne on Saturday.

Also making an Australian comeback on Friday was triple Olympic champion Libby Trickett who qualified third fastest for the women's 100m freestyle final.