David Rudisha had a vision when he went for a light training run Wednesday. The final of the men's 800 metres was barely a day away, and the Kenyan was getting worried.
"I was telling [teammate Timothy Kitum], I'm seeing everybody running his personal best apart from me," he said.
Of course, Rudisha's personal best was the world record, but he felt sluggish after two rounds of Olympic qualifying in London. But when he woke up Thursday and saw a beautiful, clear, calm day, he stopped worrying.
He went to the Olympic Stadium. And he ran.
As usual, he led from the start, pulling away with remarkable ease. He watched the split times, first at 500 metres, then 600, and he knew he was on a world-record pace.
"I decided just to push the last 200," he said.
He finished in 1 minute 40.91 seconds, taking gold and breaking his old record of 1:41.01.
In his wake, 18-year-old Nijel Amos of Botswana ran 1:41.73, a new world junior record. Kitum, just 17, finished third in 1:42.53.
In total, five runners went under 1:43.0 – a time that would win most races easily.
"Nobody has ever done the world record in the 800 metres without pace-setting, and I thought it was going to be difficult," Rudisha said. "To break the world record here is something special. I couldn't even believe it myself."
And there is likely much more to come. The 23-year-old is convinced he can run faster.
With the right conditions and a pace-setter, "I think I can still improve on that," he said with quiet confidence.
Rudisha's story has become something of legend.
His father, Daniel, won a silver medal for Kenya in the 4x400 relay at the 1968 Olympics in Mexico City and Rudisha grew up wanting to be just like his dad.
He tried the 400 at first, then the decathlon, before Brother Colm O'Connell, an Irish missionary who had been coaching track in Kenya's Rift Valley since the 1970s, suggested he try the 800 metres.
That was in 2004, and soon after, Rudisha became unstoppable.
He hasn't lost since 2009, and he broke the world record for the first time in 2010. He came to London running nearly two seconds faster this year than anyone else.
All from the front, all flat out.
He missed the 2008 Beijing Olympics because of an injury, something he said was a blessing because he wasn't mature enough. By the time he hit London, he was ready.
"I knew I could run 1:41, but breaking the world record was a different story," he said.
Thursday, he talked about his father, who couldn't make the trip to London, and how much this will mean to him.
"Before I started the race I was thinking of my father sitting in front of the TV watching me back at home. I know he's always proud of me. He's the one who made me to come this far. He's a big inspiration in my career."
Then, he reflected on new challenge. How about a race against 100- and 200-metres champion Usain Bolt over 400 metres?
"Just completely for fun," Rudisha said with a smile. "It will be great and just for fun to watch it."
In an Olympics dominated largely Bolt and his massive personality, Rudisha quietly went about his work, winning and setting a record. But he also shares something with Bolt: "I want also to become a legend later."
Like many other athletes, Jessica Smith of Canada stopped to watch. She had just run in the semi-finals of the women's 800 (she didn't advance) but had to see Rudisha run.
"It's incredible," she said. "I'm watching that it just brings out all these emotions. It's phenomenal."