(CNN) -- Defending champion Usain Bolt was sensationally disqualified for a false start in the men's 100-meter final at the world athletics championships in Daegu, South Korea, allowing fellow-Jamaican Yohan Blake to collect an unexpected gold medal.
Bolt has dominated men's sprinting since winning 100-meter and 200-meter gold at the Beijing Olympics in 2008, achieving the same feat at the world championships in Berlin the following year -- smashing the world record in the process.
And although he had not entered this year's worlds in top form, the absence through injury of rivals Asafa Powell and Tyson Gay meant he was the hot favorite to retain the first part of the sprint double.
However, the 25-year-old fell foul of the current false start rules, which state that any athlete who jumps the gun is immediately disqualified.
Bolt knew immediately he had started too early and was helped off the track, head in hands, with a packed stadium watching on in disbelief.
Once the race did eventually get under way, a muted atmosphere ensued as Blake -- a training partner of Bolt -- powered home to win in 9.92 seconds.
American Walter Dix, the Olympic bronze medallist, took silver with a time of 10.08 seconds with veteran 2003 world champion Kim Collins of St. Kitts and Nevis claiming a superb bronze medal.
"I can't find words to explain it. Usain Bolt has been there for me. I feel like I want to cry," Blake told reporters. "I felt I would win the race for Bolt."
Despite Bolt's shock exit, it proved a good day for defending world champions, with three athletes retaining the titles they won two years ago in Berlin.
American Brittney Reese retained her women's long jump title, and compatriot Trey Hardee won a second consecutive decathlon gold medal.
Meanwhile, Russian Valeriy Borchin was another to retain his title, coming home first in the men's 20-kilometer walk.
Li Yanfeng of China secured gold in the women's discus, but there was heartache for Ethiopian distance legend Kenenisa Bekele, whose attempts at a fifth consecutive men's 10,000-meter world title came to an end after he was forced to pull out of the final with groin and hip injuries.
However, the gold medal still went to Ethiopia with Ibrahim Jeilan outsprinting Briton Mo Farah in a devastating burst to the line.
Meanwhile, Oscar Pistorius made history by becoming the first amputee athlete to compete in world championships history.
The South African, who runs with carbon fiber prosthetic running blades, came third in his men's 400-meter heat to qualify for Monday's semifinal, with the final on Tuesday.