So now we know. For 12 months the Lightning Bolt had left us wondering just how fast he could strike down the home straight in the 100 metres. In the Beijing "Bird's Nest" last summer the Jamaican phenomenon shut down his engine some 25m from the line. This time in Berlin he kept flying all the way.
Unlike the Olympic final, the chest-thumping celebrations came after the line. There was a world of difference. Another world record of difference. In Beijing we all wowed as Usain Bolt stopped the trackside clock at 9.69sec. The reaction was the same last night but the figures frozen on the timepiece were different: 9.58.
We were still staring in astonishment at them as Bolt continued on his way, right round to the middle of the back straight. Such were the speed and momentum generated by the fastest man planet Earth has seen. And he hadn't even got off to the best of starts in the World Championship final. How fast might the man go when he gets that part of his sprint game up to something approaching scratch?
It is a question for another day. Possibly for a week on Friday when the young man from Trelawny Parish – he only turns 23 this coming Friday – next tackles the blue riband event at the Weltklasse Golden League meeting in Zurich.
For the time being, Bolt (below) has a World Championship gold in the bag and the 200m and 4x100m to come here in the German capital. "I was feeling good after the semis," he said. "I knew it was going to be a great race and I executed it. It's a great time, a great feeling. I feel good in myself and I knew I could do it. I came out here to do my best and I did what I had to do. There'll be no partying for me ahead of the 200m [the opening rounds of which take place tomorrow]. I need to rest up for the 200m."
In the wake of the 6ft 5in Bolt, almost unnoticed, Tyson Gay, the defending champion, took silver in 9.71sec, a US record. Bronze went to Bolt's Jamaican team-mate Asafa Powell, who clocked 9.84sec. Dwain Chambers, the sole British representative was sixth on 10.00. Those were minor details. This was another one-man Lightning Bolt Show.
And, to think: it was only in May that Bolt was upside down in a ditch after overturning his BMW M3 in Jamaica. Less than three weeks later he was in the rain in the middle of Manchester setting a world best time on a 150m track on Deansgate. Last night, in addition to pushing back the human speed barrier again, he was showing why he has redefined the meaning of Cool Runnings.
Even when he accidentally jumped the gun in his semi-final, prompting a false start warning, Bolt simply shrugged his shoulders and grinned. There was a nervous moment when the recall gun was fired a second time but it was Britain's Tyrone Edgar, not Bolt, who had twitched out of the blocks, earning the punishment of a disqualification. The race got under way at the third time of asking, Bolt easing to the front and trotting over the line an untroubled winner in a 9.89sec jog. When it came to the final two hours later, it was down to serious business.
It was a first for Bolt, a first World Championship title. In Osaka two years ago he was still strictly a 200m specialist, taking silver in that event behind Gay. The American came to Berlin as the defending 100m champion and the fastest man of the year at the shorter distance, having equalled his old American record with a 9.77sec clocking in Rome last month. He also arrived with a groin problem that had restricted his preparations.
Gay lined up last night with the initials "JO" on his vest, a tribute from the United States team to Jesse Owens, the sharecropper's son from Alabama whose 100m victory in the Olympiastadion, in front of Adolf Hitler, earned the first of his four gold medals at the 1936 Olympics.
"I ran the best I could," Gay said. "I just wanted to give my best tonight. It wasn't enough but I'm happy to have the national record. I knew I had to put out a championship performance. I gave it my best and that's all I could do."
When it comes to chasing the Lightning Bolt, the best of the rest is only good enough for a silver medal lining.