Usain Bolt capped his stunning rise to stardom with an Olympic title Saturday and, without even really trying, set a world record in the 100 meters. With world champion Tyson Gay out in the semifinals, the 21-year-old Jamaican seemingly only had Asafa Powell to beat, but when he looked around and realized he was all clear with 30 meters to go, he coasted and still set a world record of 9.69 seconds. Well behind, Richard Thompson of Trinidad and Tobago took the silver medal in 9.89, and Walter Dix of the United States was third in 9.91. Powell again crumbled under the pressure of a big competition and finished fifth. "Usain was spectacular," Powell said. "He was definitely untouchable." If athletics was looking for a defining moment to get the sport back on track after years of doping scandals, this was it. And the sellout crowd of 91,000 at the Bird's Nest let out a huge cheer, realizing it had seen something historic under the Olympic flame. With a third of the race to go, Bolt had the luxury to look right, realize he was in a class all his own, outstretch his arms, and pound his chest as he crossed the line, slicing .03 off the record he set earlier this season. Soon he settled and produced a signature move, lining up an imaginary bow and arrow and letting go of that now-famous bolt. So confident was he that he already had done the same during the presentation for the race, too. He looked like a wide-eyed giant of 1.93 meters, happy to take in the whole occasion ahead the race. Afterward, he became the happiest of Jamaicans with the biggest of grins, his canary yellow shirt disappearing in a sea of friends while reggae music blared. What was supposed to be a three-way battle turned into a one-man show never seen before. In four races in two days, not once did he push himself to the limit, yet produced the most stunning series of races. All for a guy who was hardly known outside his Caribbean nation at the start of the season. And to think his coach doubted whether to let him run the double up to a few weeks ago. Instead, Bolt produced one of the most epic races in track history. And he can make it even better. He is the overwhelming favorite for the 200, and with Powell as a teammate Jamaica is now a favorite to beat the Americans at their game - the 4x100 relay next weekend. Tense before his semifinal start, Gay was slow out of the blocks and never caught up. US teammate Darvis Patton convincingly dipped for the line and the world champion didn't, making the difference between four and five - between making the final in track's premier event and stunning disappointment. "I did my best. I don't have any excuses," Gay said. "I'm pretty upset. When I get back to the village it's probably going to set in." The Olympics were Gay's first competition since straining his hamstring at the US trials six weeks ago. It caught up with him in the third qualifying race in just over 36 hours. He refused to blame it on his hamstring though. "I'm healthy. My leg is a little sore, just from the rounds," Gay said. It means Gay's only chance at Olympic medals will come in the relays. The triple gold medalist from last year's world championships didn't qualify for the 200 when he pulled up lame at the US trials. Ahead of the fastest race at the Olympics, Russia got on the medal stand with a walk. Valeriy Borchin was the surprise winner in the 20-kilometer walk, spoiling the farewell Olympics of Jefferson Perez, the 1996 Olympic gold medalist. "Silver is silver. I once heard an athlete say that his silver tasted like gold," said Perez, one of Ecuador's greatest sportsmen. "To me, silver is silver, bronze is bronze and gold is gold." After Gay's shocking elimination, the Americans looked a lot better in the 400 hurdles. Angelo Taylor, Bershawn Jackson and Kerron Clement had the three top times to go into Monday's final. In the women's 100, the three Jamaicans all won their quarterfinals ahead of their US rivals. Much like the men, Sunday's final is seen as a showdown between the two great sprint powers. In the women's 800, Pamela Jelimo showed all of her motion, taking the lead from the start and simply running away from the pack to set the fastest time going into the final. Her Kenyan rival, world champion Janeth Jepkosgei, also ran at the front from start to finish yet faltered at the end as she held off Ukraine's Yuliya Krevsun. Still, Monday's final between the two sworn front-runners can be little else than sensational. In her farewell season, Maria Mutola made her fifth Olympic final, this time an outsider to medal after she took gold in Sydney eight years ago. One middle-distance runner fared far worse on Saturday. Bulgarian Daniela Yordanova tested positive for testosterone and will not compete at the Beijing Olympics. Defending pole vault champion Yelena Isinbayeva took off her track suit for exactly one jump, clearing the qualifying height of 4.60 meters, 44 centimeters off her world record, to advance to Monday's final. Her closest challenger, Jennifer Stuczynski of the United States, also went through. "No problems. the goal was to make qualification without expending much energy," said Isinbayeva, who already broke her own world record twice this season.