Sprint kings centre-stage for Olympics 100m

The race to be crowned world's fastest man takes centre stage at the Olympics on Sunday as Usain Bolt bids to defend his 100m title in what is being billed as potentially the quickest race in history. After an electrifying "Super Saturday," Bolt and his rivals for the blue riband event of track and field are poised to serve up more pyrotechnics as 80,000 fans pack the Olympic Stadium for the hottest ticket of the Games. Barring major surprises, the starting line-up for the 9.50pm (0850 GMT) showpiece could feature five men who have clocked a blistering 9.8sec or faster, including world record holder Bolt. The Jamaican defending champion strolled through his opening heat on Saturday, but faces a menacing threat to his supremacy from compatriot and world champion Yohan Blake, who beat Bolt in the Olympic trials. With former world record holder Asafa Powell and American duo Tyson Gay and Justin Gatlin in the field, the stage is set for a classic sprint duel. "I am the Olympic champion and I have to show the world I am the best," Bolt, 25, in a bullish eve-of-Games statement of intent. Sunday's athletics programme kicks off with the women's marathon at 11:00 am, starting and finishing in the Mall in central London, near Buckingham Palace, and taking in many of the city's most famous landmarks. The powerful Kenyan team features 2011 world champion Edna Kiplagat, last year's world silver medallist Priscah Jeptoo and Mary Keitany, the fastest woman in the world this year. The Kenyans are also hot favourites to continue their dominance in the men's 3000m steeplechase, a race they have won in every Olympics dating all the way back to Los Angeles in 1984. Ezekiel Kemboi can become the second man after defending champion Brimin Kipruto in Beijing in 2008 to win the Olympic title as reigning world champion. Sunday's action also features the final of the women's 400m with world champion Amantle Montsho looking to become Botswana's first Olympic medallist, male or female, in any sport. A total of 23 medals will be decided on Day 9 of the Games, where other highlights include the men's singles tennis final at Wimbledon between world number one Roger Federer and British hope Andy Murray. Murray will attempt to add to Britain's burgeoning gold medal haul barely one month after losing to Federer on Centre Court in the final at Wimbledon. The Scotsman also has the opportunity to win two golds in one day when he partners Laura Robson in the mixed doubles final later Sunday. "In tennis we're used to thinking the next week we have another chance. But with the Olympics you're not guaranteed another chance," said Murray. "Anything can happen with your career. That's why every match is important here." The final two medals in one of the Olympics other racquet sports, badminton, will be decided at Wembley Arena where China's world number one Lin Dan faces Malaysian rival Lee Chong Wei in the latest instalment of their long rivalry. In men's and women's artistic gymnastics, where the apparatus finals for men's floor and pommel horse take place either side of the women's vault. Elsewhere, women's boxing will make its debut in Olympic competition for the first time with the opening bouts in the women's flyweight and lightweight categories.