Usain Bolt was again left to rue a poor start as he was stunned by training partner Yohan Blake in the 100 metres at the Jamaican National Championships and Olympic trials.
Blake clocked the fastest time in the world this year to take victory in 9.75 seconds, with Bolt, who was very slow out of the blocks, battling back to finish second in 9.86secs.
Asafa Powell was third in 9.88 at the National Stadium in Kingston to also qualify for the London Games.
The world record holder's loss was only his second in four years, not including his false start in the 100m final at last year's World Championships in Daegu where Blake won gold.
This was the pair's first meeting since that race. It was also Bolt's first defeat on home soil since 2004.
Blake knocked his 25-year-old rival off the top of the world rankings - Bolt's best this year is 9.76 set in Rome last month - as the 22-year-old proved his fellow Jamaican is anything but a certainty to retain his Olympic crown.
Commenting on his start, Bolt, whose last defeat came to American Tyson Gay in Stockholm in August 2010, said on www.usainbolt.com: "I had to ignore it, I had trouble getting out, but I kept feeling like I could not give up."
Blake, dubbed 'The Beast' because of his prodigious work ethic, shattered his personal best of 9.82.
He said on www.iaaf.com: "I am happy with becoming the national champion. I won the World Championships last year, now the national championships, so I now go into the Olympic Games."
Powell revealed after the race he had a torn groin, which is likely to hinder his Olympic preparations.
Powell, who missed last year's World Championships with a groin problem, Tweeted: "Tore my groin on the 1st round of the trials. Your strength & prayers willed me through the pain & on to the London Olympics. One love!"
All eight men in the final met the Olympic A standard of 10.18. Only two Britons have achieved that mark this year.
Bolt and Blake are set for another showdown in the 200m final tomorrow as both cruised into the semi-finals today.
Bolt won his heat in 21.21 and Blake his in 21.43, both running into strong headwinds.
Bolt is the Olympic and world champion over 200m, but Blake proved his credentials over the distance last September by running the second fastest time ever over the distance, after Bolt, clocking 19.26 in Brussels.
He also leads the 2012 rankings with 19.91.
Defending women's 100m champion Shelly-Ann Fraser-Pryce broke the national record as she won her final in 10.70, which was also a world-leading time.
She was joined on the team by Athens and Beijing 200m winner Veronica Campbell-Brown who ran 10.82.
Kerron Stewart, who was joint second in Beijing, finished third while the other woman to take a share of silver in 2008, Sherone Simpson, could only finish fourth.
Olympic 400m hurdles champion Melaine Walker also won her final, running 54.77.