Sally Pearson is hopeful of finding some speed and favourable conditions in Sydney on Saturday night as she continues her pursuit of the Australian record books.

After a bright start to her domestic season in Brisbane in February, the Beijing Olympic 100m hurdles silver medallist has failed to find top form since, although she has remained undefeated.

Pearson was particularly disappointed by her results in Melbourne earlier this month, when her times in the 100m and 200m sprints were well below her best.

The Queenslander, whose best 100m time is 11.14 seconds, is targeting Melinda Gainsford-Taylor's long-standing national record of 11.12, but could only manage 11.52 in Melbourne.

"I have no idea, I really don't know," she said when asked about her sluggish times in Melbourne.

"It's difficult, I've never run fast in Melbourne and don't know why, I don't have any excuses for it.

"I was in good shape and unfortunately the time didn't come with it.

"Hopefully the conditions on Saturday, which I heard aren't that great, will be okay and I can run faster.

"Conditions are a huge part of sprinting.

"Hopefully it'll be a bit better on Saturday and a bit warmer."

Pearson is hopeful visiting sprinter Miki Barber can push her towards some better times at the Sydney Track Classic after the American also struggled in Melbourne.

Barber has thrown the challenge down to Pearson, declaring she is targeting a 100m-200m double on Saturday night.

As well as the 100m record, Pearson is also zeroing in on a sub-23 second run in the 200m. Her personal best in the event is 23.02 and she has been working on some changes to her race strategy.

"We've been changing a few things," Pearson said. "Not technical things, more about a race plan, and I didn't stick with it at the Melbourne meet.

"I was running against American girls and I didn't know what sort of shape they were in.

"I took the first 100 a little too fast and couldn't keep up the speed for the last hundred.

"I was in a lot of pain at the end."

While Pearson hasn't been able to put it all together yet to set some new PBs, she knows she is more than capable.

"Definitely. My training proves that I can run that fast, it's just a matter of doing it on the day," she said.

Pearson will have a busy program on Saturday, hoping to also help the Australian 4x100m relay team qualify for the August world championships.

James Dampney
AAP