David Rudisha became the first athlete to set a new world record on the track at London 2012 as he won 800m gold.
The 23-year-old Kenyan stormed to victory in his debut Olympic final to become the first man inside one minute 41 seconds, clocking 1:40.91.
Botswana 18-year-old Nijel Amos took silver, with another teenager, Kenya’s Timothy Kitum, in bronze.
Britain’s Andrew Osagie was in eighth place but still clocked a personal best of 1:43.77.
Reigning world champion Rudisha led from the off, running an opening lap of 49.28 seconds and storming further clear down the back straight to beat his own world record.
With the rest of the field dragged along by his pace, only Abukaker Kaki in seventh failed to record a personal best.
Rudisha told BBC Sport: "Wow! I’m very happy. This is the moment I have been waiting for for a very long time. To come here and to break the world record is something unbelievable.
"I was well-prepared and I had no doubt about winning. Today the weather was beautiful and I decided just to go for it."
But the new world record holder believes he can go even faster.
He said: "After running two rounds before the final I got a little bit tired. I told the physio yesterday that I was feeling sore after the semis, so if I can get fresh then I can still improve on that."
Earlier on Thursday 2012 chief Lord Coe said Rudisha was "the most impressive track and field athlete at these Games".
Rudisha said: "Lord Coe is a very good friend of mine and earlier, in February, he took me round this stadium. That was good for me. I wanted to come here and make him proud."
In Amos and Kitum, 17, the future of the event looks in good hands but whether anyone can get near the dominant Rudisha before the next Games in Rio looks unlikely.
Amos clocked 1:41.73 – the 11th fastest 800m of all time – to become the fourth-fastest man ever over the distance. Only Rudisha, Wilson Kipketer and 2012 Games chief Seb Coe have run two laps of the track faster.
Rudisha has set the three fastest 800m times of all time and managed six of the fastest eight 800m ever.
His pace was consistent throughout, clocking 23 seconds for the first 200m, 25 for the second, 25 for the third, and 26.1 for the final quarter.