Usain Bolt raced to redemption in 19.40 golden seconds on Saturday to retain his world 200 metres title while Anna Chicherova ended Blanka Vlasic's four-year run as high jump world champion.

"Believe" Bolt mouthed to the cameras as he celebrated his win. Nobody had stopped believing, even after he was disqualified from the 100 metres final last Sunday, but certainly there was a sense that the natural order had been restored.

If anyone in athletics can match Bolt for sheer charisma, it is Vlasic but the Croatian, who was aiming for a third successive world title, found that counted for nothing against a rival in the form of her life.

Allyson Felix gathered her first gold medal of the 13th championships, after failing to win the 200-400 double, when the United States women won the 4x400m relay for the third time in a row.

Australia left it late to win a gold medal in Daegu, but finally succeeded through Sally Pearson's barnstorming run in the 100 metres hurdles. She finished in 12.28 seconds to set a championship record and become the fourth fastest woman ever.

"I knew when I got to the final I could do anything," Pearson said after completing a 17th straight win.

For for all the drama dotted around Daegu's cavernous stadium, there was no mistaking whose show it was and the world's fastest man conducted proceedings like a ringmaster.

From the second Bolt languidly entered the arena, all eyes were on him and he did not disappoint.

First bumping fists with a girl volunteer he then went through his now familiar routine of fashioning his hair, gesturing to the TV cameras and, in a new twist for Saturday, smoothing his eyebrows.

His time was not close to his world record of 19.19 set at the last world championships two years ago, but it was still the fastest of the year.

Silver medallist Walter Dix recorded a season's best 19.70 and bronze medallist Frenchman Christophe Lemaitre clocked a national record 19.80.

"I feel great. I wasn't running angry, I was running hard just to say to fans sorry about the 100 metres," Bolt told reporters.

"I came out here to do my best and prove to them. At the start I did not panic, 19.40 for me, it is a good time. I am not in my best shape, but it is all about fun and enjoyment."

Perennial bridesmaid Chicherova finally got the better of Vlasic, taking the title after finishing runner-up to the Croatian in the 2007 and 2009 world championships.

As competitors fell away one by one, the battle developed into a straight shootout between the pair.

Vlasic, who confirmed her attendance very late due to a knee injury, jumped her season's best of 2.03 metres but was matched by Chicherova.

When neither was able to manage 2.05, the title went to the Russian who, with her white socks pulled up to her knees, had a perfect five jumps at five previous heights.

Despite her tears at the finish, Vlasic looked for positives.

"Twenty days ago I jumped 1.90 metres in training and I was crying like hell. I was, like, I don't want to put myself through this," she said. "But now I'm delighted, it was the 100th time over two metres."

The American women's triumph in the 4x400 was the nation's 10th gold medal of the championships and they sit proudly on top of the medals' standings.

"It really feels great," Felix said. "I enjoy running a relay. We have such depth," she added, confirming she was still planning to run the 4x100m relay on Sunday.

Teammate Sanya Richards-Ross, who ran the first leg, said: "It is always great to end the competition with a gold medal."

But of course it wasn't long before the focus again turned to that man Bolt.

"You really like to watch and see what he is going to do next," Felix smiled. "He always puts on a show."

Germany's Matthias De Zordo also put on a show, clinching javelin gold with his first throw of 86.27 metres, a season's best. Norwegian Olympic champion and 2009 world champion Andreas Thorkildsen could not overhaul him and had to settle for silver.

In the men's 1,500 metres, Olympic champion Asbel Kiprop outsprinted compatriot Silas Kiplagat for gold. His win in three minutes 35.69 seconds clinched Kenya's sixth gold in Daegu.

"It makes me feel very happy to be the first Kenyan to win the 1,500 metres," Kiprop said.

Kiprop's gold was Kenya's sixth, a record haul at a Worlds. "It shows Kenya is the best," he said.