Down on speed: Sally Pearson is not at her best.

Down on speed: Sally Pearson is not at her best. Photo: John Veage

Sally Pearson is satisfied her comeback from injury is on track three weeks out from the Commonwealth Games, despite another disappointing performance in the 100 metre hurdles in Paris.

The reigning Olympic and Commonwealth champion faded to sixth at the Diamond League meet in the French capital, but at least improved on last week's slow time of 13.19 in her return from hamstring problems in Belgium.

American Dawn Harper-Nelson - who finished second to Pearson at the London Olympics - ran the fastest time of the year to blitz a hot Paris field in 12.44 seconds, with her Australian nemesis clocking 12.89.

But while Pearson's preparations for the Glasgow Games have been far from ideal, Australian discus champion Dani Samuels continues to go from strength to strength after throwing over 67 metres for the third time this year to claim an impressive second in Paris.

Samuels led throughout before a final-round throw of 68.48 from current world No.1 Sandra Perkovic of Croatia snatched the win - edging out the Sydneysider who responded with a final throw of 67.40.

Ranked second in the world, Samuels is in near career-best form and will go to Glasgow as overwhelming favourite.

Pearson, with her left thigh heavily strapped, got out of the blocks well but then struggled in the back half of the race as Harper-Nelson and fellow Americans Queen Harrison (12.46) and Lolo Jones (12.68) surged.

The 27-year-old Queenslander has just next week's Diamond League meet in Glasgow and then an event in Luzern Switzerland to get things right before she joins the Australian Commonwealth Games camp on July 21.

After missing events in Rome and New York early in June due to hamstring soreness, Pearson said in a brief post on her twitter feed that she feels her rhythm is coming back

"It's coming ... satisfied 12.89 thank you Paris "

In her current form, Pearson will face stiff competition at the Commonwealth Games from English athlete Tiffany Porter - who ran 12.72 to finish fifth in Paris - and Canadian Angela Whyte - who ran a 12.89 in April and finished second to Pearson at the 2010 Delhi Games.

Pearson is yet to make a final decision on whether she will also contest the 100m flat race at the Commonwealth Games, but Australia's other great hope in that distance Melissa Breen warmed-up nicely by taking out the Memorial Leon Buyle event in Belgium in 11.33.

In the men's, Jarrod Geddes placed third in the men's 100 in 10.28.

Victorian middle distance runner Alex Rowe took out the men's 800m race in a new personal best time of 1:44.74 - putting him in elite company as one of only four Australian athletes ever to have run sub-1:45.

Decathlete Jack Stein took the chance to compete in the men's javelin and discus in Belgium - finishing fourth and third respectively.

Elsewhere, Queensland pole vaulter Alana Boyd cleared a new season's best of 4.65 to win the Bauhaus Gala meet in Germany.

AAP