By Mitch Phillips

BERLIN (Reuters) - Usain Bolt shattered his own 200 meters world record by the same unbelievable margin he sliced off his 100 mark on Sunday to secure his place as the greatest sprinter the world has ever seen.

One year exactly after posting 19.30 to beat Michael Johnson's "untouchable" 19.32 from the Atlanta Olympics he ran 19.19 to scythe 11 hundredths of a second off the mark just as he did in the 100 on Sunday when he posted 9.58.

The Jamaican said it was "not a good race" but his amazing performance easily secured him the world title.

Bolt, who turns 23 on Saturday, is now the world record holder and world and Olympic champion in both sprints -- something no other athlete has achieved.

"I was trying, I was dying," he said. "It wasn't a good race I can say but it was a fast one."

Jamaica's gold rush continued in the women's 400 hurdles when Olympic champion Melanie Walker ran the second-fastest time ever -- 52.42 seconds -- to take the island's tally to five.

Ryan Brathwaite of Barbados won the 110 hurdles in a blanket finish with the first three divided by one hundredth of a second.

Croatia's Blanka Vlasic went some way to making up for her Olympic disappointment when she retained the women's high jump title with a leap of 2.04 meters.

RELAXED BOLT

Bolt, as ever, was ridiculously relaxed ahead of the 200. He had good reason as within half a dozen of his galloping strides he had run down Panama's Alonso Edward, who went on to take second in 19.81.

Bolt romped down the home straight, the effort stitched across his grimacing face, and crossed the line pointing at the clock.

"I did well for myself and I'm on my way to becoming a legend," he said, to universal agreement.

"We call him 'Insane Bolt,' said Wallace Spearmon of the U.S., who took third in 19.85.

In the 400 hurdles, Walker produced a storming last 100 to overtake American Lashinda Demus and post a time bettered only by the 52.34 of Russian Yuliya Pechonkina.

In the 110 hurdles Brathwaite, 21, took the honors by the thickness of his vest in 13.14.

Terrence Trammell had to settle for his third world silver to go with two from the Olympics as he finished ahead of compatriot David Payne after both finished in 13.15.

Marshevet Hooker, the fastest qualifier into the semi-finals of the women's 200, pulled up injured midway through to miss out on Friday's final.

Debbie Ferguson-McKenzie was the fastest qualifier but Jamaican trio Veronica Campbell-Brown, Anneisha McLaughlin and Simone Facey, together with surviving Americans Muna Lee and Allyson Felix, should all be in the mix.

DOUBLE VISION

Bolt is not the only man with double vision as Kenenisa Bekele and Yusuf Saad Kamel remain on course to join him.

Bekele, who won his fourth successive 10,000 gold on Saturday, was the fastest qualifier for the 5,000 final and looks a good bet to become the first man to complete the long-distance double at the world championships.

Kamel claimed the 1,500 on Wednesday night and was up early to win his heat and progress to the semi-finals of the 800 where he hopes to follow in the footsteps of his father Billy Konchella, who won the 800 world title in 1987 and 1991.

Following the news that the 18-year-old South African 800 winner Caster Semenya is undergoing gender verification tests, officials in her home country leapt to her defense.

"I am not going to let that girl be humiliated in the manner she was humiliated because she has not committed a crime whatsoever," said Athletics South Africa president Leonard Chuene.

Friday's morning session features only one event but it is the longest in the programme, the men's 50km walk.

The evening sees the finals of the women's 200m, men's 400m, women's discus and men's high jump.

(Editing by Ken Ferris)