Triple Olympic champion Usain Bolt of Jamaica shattered his 200 metres world record in Berlin when he clocked 19.19 seconds to win gold at the World Championships.
He beat the mark of 19.30 he had set a year ago to the day at the Beijing Olympics.
Bolt has become the only man ever to hold the 100 and 200 Olympic and world titles as well as the world records at the same time.
Panama's Alonso Edward was second with a time of 19.81 and American Wallace Spearmon third.
The top five sprinters all clocked under 20 seconds.
"I had nothing to lose," Bolt said. "I went out there and just did my best.
"I was kind of tired for yesterday, but in the warm-ups I was feeling good so I decided what the heck -- let's come out here and try for the world record.
"I ran hard and I got it, and I'm proud of myself. You could see the look on my face, I was really trying hard, I was digging, I was giving everything I got.
"It was all for the fans - I knew they were coming out (to see something special)."
Bolt, a day short of his 23rd birthday, was unfazed by a false start triggered by Frenchman David Alerte and played up to the cameras in his usual way.
Once the starter's pistol went off, the Jamaican bolted from the blocks and within 20 metres he had grabbed the lead he would never relinquish.
He raced down the straight well ahead of everyone else, with only the clock to beat. He caught a glimpse of his time just at the finish line and saw that 11 hundredths had been knocked off yet again.
Bolt had also demolished his own 100m world record on Sunday, taking off 11 hundredths to clock the stunning time of 9.58.