Allyson Felix completed a hat-trick of women’s 200 metres world titles on Friday but fellow American Jeremy Wariner’s bid to match her in the men’s 400 failed when he lost again to compatriot LaShawn Merritt.

Smooth-striding Felix triumphed in 22.02 seconds to beat double Olympic champion Veronica Campbell-Brown of Jamaica while Merritt’s success completed a personal double after he beat Wariner having already taken his Olympic title last year.

Back on top

The victories took the U.S. back above Jamaica to the top of the medals table with six golds but the night turned sour for it when its men’s 4x100 relay team was disqualified.

Russia’s Yaroslav Rybakov won the men’s high jump and Australian Dani Samuels the women’s discus.

Felix, twice an Olympic silver medallist, delivered a smooth run on a track sodden by a thunderstorm. “I’ve worked so hard and I’ve defended my title -- I cannot ask for more,” she said.

Campbell-Brown was second in 22.35 ahead of Debbie Ferguson-McKenzie of the Bahamas (22.41).

While Felix still reigns, Wariner has been doubly deposed as the one-lap king by his one-time lieutenant.

Merritt emerged from Wariner’s shadow in Beijing when he won the Olympic title and he ran a similarly patient race on Friday, coming strong in the last 100 after Wariner had gone out hard.

Merritt finished in 44.06 seconds to the 44.60 of his rival, with Rennie Quow of Trinidad & Tobago third in 45.02.

“It was all about putting it from my head to the track as I had already won the race in my heart,” Merritt said. “At 350 I knew I had won.”

Relay team disqualified

In the sprint relay, Olympic champion and world record holder Jamaica, without Usain Bolt or Asafa Powell, qualified second in its heat behind Italy.

The United States, without Tyson Gay, won its heat impressively in 37.97 seconds, having dropped the baton in the Olympic semifinals.

However the U.S., which also messed up in the 1995, 1997 and 2005 worlds, was then disqualified for a changeover outside the box. A U.S. appeal against the decision was rejected.

Rybakov won an exciting high jump final on the countback after the top four all cleared 2.32 metres. Kyriakos Ioannou took rare silver for Cyprus while Sylwester Bednarek of Poland and Germany’s Raul Spank shared bronze.

Surprise winner

Samuels, 21, was a surprise discus winner as she pulled out a big personal best 65.44-metre effort in the fifth round to overhaul Cuba’s Yarelis Barrios (65.31) and veteran Romanian Nicoleta Grasu (65.20).

Yusuf Saad Kamel, Bahrain’s newly-crowned 1,500 champion, qualified fastest (1:45.01) for Sunday’s 800 final.

It was a bad race for Sudan though as Abubaker Kaki, fastest over the distance in the world this year, tripped early in his semifinal and failed to progress while Olympic silver medallist Ismail Ahmed Ismail dropped out at the bell in his heat.

Olympic and defending champion Maryam Yusuf Jamal was fastest into the women’s 1,500 final but Olympic silver medallist Iryna Lishchynska dropped out during her semifinals.

Bolt celebrates birthday

Bolt continued to expand his reputation as not only the most impressive but the most popular man in the sport as he took time out on his 23rd birthday to sign hundreds of autographs for delighted fans in a 40-minute stadium walkabout.

He was then on the receiving end of a chorus of “Happy Birthday” from the crowd after receiving his 200 metres gold.

The results:

Men: 400m: 1. LaShawn Merritt (USA) 44.06s, 2. Jeremy Wariner (USA) 44.60, 3. Renny Quow (Tri) 45.02.

High jump: 1. Yaroslav Rybakov (Rus) 2.32m, 2. Kyriakos Ioannou (Cyp) 2.32, 3. Sylwester Bednarek (Pol) & Raul Spank (Ger) 2.32 (tie).

Women: 200m: 1. Allyson Felix (USA) 22.02s, 2. Veronica Campbell-Brown (Jam) 22.35, 3. Debbie Ferguson-McKenzie (Bah) 22.41.

Discus: 1. Dani Samuels (Aus) 65.44m, 2. Yarelis Barrios (Cub) 65.31, 3. Nicoleta Grasu (Rom) 65.20.

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