BEIJING (AP) The Latest from the IAAF world championships (all times local):
After being taken down by a cameraman following his latest gold-medal performance, Usain Bolt jokingly blamed rival Justin Gatlin for the accident.
''The rumor I'm trying to start right now is that Justin Gatlin paid him off. So, that's what I'm going with,'' Bolt said, with Gatlin sitting right next to him.
The offending cameraman hit a metal rail on the side of the track and veered right into the back of Bolt. He hit the Jamaican in the legs and both fell backward onto the track.
Bolt won his second gold medal of the world championships on Thursday, taking first in the 200 meters at the Bird's Nest. Like in the 100, Gatlin finished second.
Tori Bowie, the bronze medalist in the 100 meters at the world championships, has been informed she cannot run in the relays for the Americans because she was absent from a training camp in Japan earlier this month.
According to Bowie's agent, Bowie attended a relay camp in Monaco earlier this summer, but because she missed a camp in Narita, Japan, in the lead-up to worlds, USA Track and Field informed the sprinter it was against policy to allow her to run in the relays.
''Of course, she would love to run the relay and support her country,'' said Bowie's agent, Kimberly Holland.
USATF did not immediately respond to emails from The Associated Press seeking information about Bowie's status.
Shortly after winning another 200-meter race at the world championships, Usain Bolt was accidentally taken down by a clumsy cameraman on a two-wheel vehicle.
With Bolt taking in the adoration of the crowd at the Bird's Nest, the cameraman hit a metal rail on the side of the track and veered right into Bolt. He hit Bolt in the legs from behind and both fell backward to the track.
Bolt appeared unscathed.
An upcoming kidney transplant is weighing on American hurdler Aries Merritt. But racing provides a nice distraction as the Olympic champion advanced to the final at the world championships.
The world-record holder had the fastest time in the semifinal round.
Four days after the final, Merritt will have surgery back home in Phoenix.
''What happens after the finish line (Friday) definitely scares me,'' Merritt said. ''It's tough and scary. I can't focus on that right now.
''I have to take my mind off of what's going on with my physical condition and be mentally tough in this final.''
Usain Bolt won the 200 meters in 19.55 seconds Thursday to complete another sprint double at the world championships, again holding off Justin Gatlin.
At least the trip to the hospital in an ambulance gave South African 400-meter champion Wayde van Niekerk a chance to catch his breath.
He was that exhausted after his race at the world championships. Doing just fine a day later, van Niekerk returned to the Bird's Nest on Thursday to receive his gold medal.
''I tried to go as fast as possible, to try to get to the finish line as quick as possible,'' van Niekerk said. ''I knew I had to give it my all.''
Van Niekerk got tired again - of doing interviews. All this attention takes some getting used to.
The price of fame after quite a performance.
Van Niekerk needed to reach down deep to hold off Olympic champions LaShawn Merritt and Kirani James. That left him breathless. He was taken to the hospital for evaluation.
Looking back, van Niekerk said his biggest mistake was sitting down so soon after the race and that if he had remained standing, he would've been able to take a customary victory lap.
''I'm just grateful for the fact I got the medal,'' he said. ''This was taken way more out of proportion than what it was. I was just exhausted.''
Unbeaten this year, defending champion Eunice Sum of Kenya finished third in her semifinal heat in the 800 meters at the world championships and still qualified for Saturday's final.
Sum led from the start on Thursday but she let Melissa Bishop of Canada and Marina Arzamasova of Belarus sneak past her at the line, with Bishop clocking 1 minute, 57.52 seconds. The top three finished within .04 seconds of each other.
With only two automatic qualifiers from each heat, Sum went through to Saturday's final with the best losing time of 1:57.56.
Caster Semenya, the 2009 champion and the 2012 Olympic silver medalist, finished last in her semifinal heat and was elimianted.
Allyson Felix won the 400 meters in 49.26 seconds on Thursday to earn her ninth world championship gold medal and match the total of Usain Bolt.
Ten years after she won her first gold, a 200-meter title in Helsinki, Felix ran the fastest time in the world this year to win in Beijing.
Shaunae Miller of Bahamas won silver in 49.67 and Shericka Jackson of Jamaica took bronze in 49.99.
Christian Taylor produced the second-best triple jump of all time to win the United States' second gold medal of the world championships, recording 18.21 meters with his final attempt.
The 2012 Olympic gold medalist and 2011 world champion has been in a duel all season with Pedro Pablo Pichardo of Cuba, with both clearing the 18-meter mark in the last two months to raise the prospect of the world record falling in Beijing.
In the end, Taylor narrowly missed the 18.29 mark which Jonathan Edwards set the world championships at Gotenburg in 1995.
Pichardo took silver at 17.73, also saving his best for the last round. Nelson Evora of Portugal jumped 17.52 with his final attempt to edge Omar Craddock (17.37) for the bronze.
Anita Wlodarczyk broke the championship record twice on consecutive throws to win her second world title in the women's hammer throw with a mark of 80.85 meters.
The 30-year-old Polish thrower set the world record of 81.08 on Aug. 1 and seemed to be on course to break it again when she improved with each of her first four attempts.
She recorded 78.52 with her second attempt after a relatively gentle opener of 74.40.
Wlodarczyk broke the meet record with her third attempt at 80.27, improving on the 78.80 set by Tatyana Beloborodova of Russia in Moscow in 2013, and improved it again with a mark of 80.85 on her fourth throw. Her fifth attempt broke a sequence of round-by-round improvements with a mark of 79.31.
Wlodarczyk, the runner-up at the last Olympics and world championships, finished off with a foul.
Zhang Wenxiu of China won the silver medal in 76.33, ending a sequence of three consecutive bronze medals at the worlds. Alexandra Tavernier of France was third at 74.02.
Dina Asher-Smith of Britain qualified fastest for the women's 200-meter final at the world championships with a personal best time 22.12 seconds, holding off Jeneba Tarmoh (22.38) and Veronica Campbell-Brown (22.47).
The final will feature three Jamaicans and two Americans, as well as Asher-Smith, Dafne Schippers of the Netherlands and Ivet Lalova-Collio of Bulgaria.
Elaine Thompson of Jamaica won the opening semifinal heat in 22.13 and was second-fastest overall, followed by Candyce McGrone in 22.26.
Schippers won the second semifinal heat in 22.36 seconds, coasting for the last 60 meters, with Sherone Simpson qualifying in 22.53.
If pole vaulter Fabiana Murer thought winning a silver medal at world championships was cool, imagine what will happen if she wins a gold at the Olympics.
Murer is from Brazil, and the Olympics are in Rio de Janeiro next August.
After receiving her silver medal Thursday evening, she spent about a half-hour hanging around the Bird's Nest taking pictures and sharing hugs with coaches and others from the Brazilian team.
The 34-year-old Murer, who will retire after the Olympics, said she's enjoying this and is already thinking about what will be her last, and biggest, meet.
''It'll be an amazing competition - to compete for my country, and have my home crowd cheer for me,'' Murer said. ''I think it helps you, and can help the Brazilians win more medals.''
Olympic champion Aires Merritt qualified fastest for the 110-meter hurdles final at the world championships, winning his semifinal heat in a season-best 13.08 seconds.
Sergei Shubenkov of Russia won his semifinal heat in 13.09 to record the second-fastest time.
Defending champion David Oliver had the sixth-fastest time, placing second in his heat in and getting an automatic qualifier in 13.17.
The influence of Jesse Owens will extend to the world championships, where the daughter of the Olympic great will present the gold medal to the winning team in the men's 4x100-meter relay on Sunday.
The relay could be a duel between modern great Usain Bolt and his Jamaican team and the U.S. squad.
Beverly Owens Prather is in Beijing representing The Jesse Owens Foundation, which will commemorate the signing of an agreement with the IAAF's Social Responsibility program during the meet.
Owens, who won the 100, 200, long jump and 4x100-meter relay at the 1936 Olympics in Berlin, will be featured in a film due for release in April.
In the film, Stephan James will play the role of Owens, who died in 1980.
The dancing hurdler, Michelle Jenneke, progressed to the semifinals at the world championships.
The 22-year-old Australian advanced alongside Dawn Harper-Nelson, who won the Olympic gold medal at the Bird's Nest in 2008.
Jenneke's warmup dance behind the starting blocks at the 2012 world junior championships was an internet hit. On the competitive side, she's ranked No. 2 in Australia behind Olympic champion Sally Pearson, who is skipping the worlds because of injury.
On Thursday, Jenneke advanced with a time of 13.02 seconds running in the lane beside Harper-Nelson, who won their heat in 12.79.
Brianna Rollins qualified fastest in 12.67, followed by Tiffany Porter of Britain in 12.73 and Jamaican sisters Danielle and Shermaine Williams.
In the women's long jump, an era came to an end.
Brittney Reese of the United States had won every global outdoor competition since the 2009 world championships, and at 28 the defending Olympic champion was seeking to extend that streak at the worlds in Beijing.
The three-time defending champion, however, has been struggling with a bad back at the Bird's Nest and failed to make it through qualifying with a best jump of 6.39 meters, well short of the qualifying mark of 6.75.
Olympic champion Anna Chicherova of Russia and former world champion Blanka Vlasic of Croatia were among the favorites to qualify for the women's high jump final at the world championships.
All 13 jumpers who advanced cleared the same height of 1.92 meters.
The 33-year-old Chicherova, who took gold at the 2012 London Olympics and bronze at the 2008 Beijing Games, has a world-leading mark of 2.03 meters this year.
Vlasic, who won silver at the 2008 Olympics, looked to be returning to her earlier form with a leap of 1.97 this year before injuries curtailed her preparations coming into the worlds.
Also moving through to the final was 36-year-old Ruth Beitia, who is competing in her seventh world championships. Beitia had planned to retire at the end of 2012, but changed her mind and won a bronze medal at the 2013 worlds in Moscow.
The Spaniard has cleared 2.0 meters this year.
Another veteran, 41-year-old Venelina Veneva-Mateeva of Bulgaria, failed to make the final in her ninth world championships. Chaunte Lowe, the only American in the field, also did not advance after failing to clear her opening height of 1.80.
Katarina Johnson-Thompson finally recorded a mark in the long jump pit at the world championships, four days after fouling out in the same discipline during the heptathlon while she was in second place.
Johnson-Thompson was up early in the qualifying round for the long jump on Thursday, and opened with a mark of 6.54 meters. Three fouls in the same pit last Sunday resulted in her slipping from gold-medal contention to out-of-contention in a heptathlon won by British teammate Jessica Ennis-Hill.
Two days after winning the 1,500 meters at the world championships, Genzebe Dibaba is through to the final of the 5,000 and looking for another Dibaba double at the Bird's Nest.
Tirunesh Dibaba, Genzebe's older sister, won a long-distance double at the 2008 Beijing Olympics, and now the younger sibling is one victory away from a similar feat.
Under the morning sun at the Bird's Nest and with five assured qualifiers from her heat, Dibaba was certain to go through when the lead pack had dwindled to only five runners on the final lap. Dibaba still put in a little kick for home to win the heat in 15 minutes, 20.82 seconds, more than a minute behind the world record of big sister Tirunesh.
Day 6 of the world championships will culminate with Usain Bolt's bid for another sprint double when he runs in the final of the 200 meters.
Justin Gatlin, who wasn't beaten in the 100 all season until he was edged by Bolt in Sunday's final, will be there again among the contenders trying to stop the Jamaican dominance in the sprints.
That is one of four finals set for Thursday, with the others in the men's triple jump and the women's 400 and hammer throw.
Competition commenced in qualifying for the men's discus and the women's high jump and 5,000.