Ryan Lochte held off Olympic champion Michael Phelps is a thrilling end to win the 200m freestyle at the World Championships in Shanghai men. Lochte, 26, clocked one minute 44.44 seconds for gold, with other American Phelps taking silver in 1:44.79, ahead of defending champion Paul Biedermann.
French duo Jeremy and Camille Lacourt Stravius shared the gold men's 100m backstroke after a dead heat.
Britain Liam Tancock, who won the defense of 50, was back in the sixth.
France had never won a title in any men's swimming World Championships, but Stravius and clocked 52.76 seconds Lacourt, Ryosuke Irie ahead of Japan, who won the bronze in 52.98.
"For me it was a lot of time to reach the final," said Tancock later. "In a world in sixth place is not bad. I have a couple of days to rest and recover from 50m, and I look forward to that."
Phelps, Olympic champion and former world record holder, had led to the first half of the final of the 200m freestyle, but Lochte surged through from third place to win a narrow victory.
"Michael and I have battled head-to-head in almost eight years now," Lochte said. "It was back and forth, and it is certainly a good rivalry."
Women's 100 meters backstroke final was equally dramatic, with China's Zhao Jing winning in 59.05secs, beating Russia's Anastasia Zueva of only one hundredth of a second.
Natalie Coughlin, and the United States finished third, while Britain's Lizzie Simmonds finished seventh, his performance at the same event in Rome in 2009, when Gemma Spofforth took the gold.
Spofforth no progress Monday's heats after the destruction of their preparations for the disease.
"I was in a lane that was never going to be the center of the action, but it was hard for me to swim," said Simmonds. "I was so excited to be in the end, I had a good race and I really enjoyed it."
British Rock Partners Michael could not reach the final of the 200m butterfly, after passing the slowest time in the semifinals.
Rock, who was removed from qualifying in 16th place, said: "I am disappointed that he could not produce the result I wanted, I do not apologize, but I was sick and having stomach pains. Did not have the best pair of days. "
Phelps, who could still win five gold medals in Shanghai has successfully completed the third best time behind Takeshi Matsuda of Japan and China Chen Yin.
Rebecca Adlington and Jo Jackson were able to get the heat out of women's 200m freestyle.
The race for four length is not a major event Adlington, but Jackson was disappointed to finish seventh in his heat and 23 overall with a time of 1:59:40 seconds. Adlington finished eighth in the same race, finishing 0.4 seconds back.
Rebecca Soni of the United States defended his title in the 100 breast, ahead of Australian Olympic champion Leisel Jones and Ji Liping China, who took silver and bronze.