Australia's Jana Pittman has qualified for Thursday's final of the 400 metres hurdles at the world athletics championships.

Pittman fought back to win her semi-final in a time of 53.77secs, ahead of American Sandra Glover who finished in 53.90 after leading over the last hurdle.

But Pittman's main rival for gold, Russian world record holder Yuliya Pechonkina, looked unbeatable as she cruised home in her semi in 53.58, with European champion Ionela Tirlea from Romania finishing a distant second in 54.84.

Pechonkina, who set the world record of 52.34 at the Russian national titles on August 8, was as dominant as she was in her heat and is growing in stature as a clear favourite for gold.

Her time took over from Pittman's 53.62 as the fastest in the world this year.

Glover took Pittman out hard in their race and took over the lead at the 10th hurdle, but the 20-year-old Australian pushed home hard and later admitted she had been outraced.

"Phil (coach Phil King) wanted me to take it easy around the top bend and I did that but I was outraced today," she said.

"So probably I shouldn't have relaxed so much down the back straight, I wanted to have a little bit left if she did challenge me at the 10th hurdle and I was strong enough to keep in front.

"I'm really fit, I would have liked to have run a bit faster tonight but a win's a win."

Canberra giant Stuart Rendell came 10th in final of the hammer throw with a best heave of 75.72, with gold medallist Ivan Tikhon from Belarus throwing 83.05.

Brought to you by AAP © 2024 AAP