Bolt and Gatlin cruise through 100 metres heats in Beijing
Justin Gatlin responded to boos from the Beijing crowd by storming to 9.83 seconds in the heats of the 100 metres at the World Championships.
The two-time drug cheat, cast as athletics' number one villain, especially in the wake of the doping crisis which has engulfed the sport in recent weeks, looked mightily impressive in qualifying fastest for Sunday's semi-finals at the Bird's Nest stadium.
Gatlin's introduction was greeted with audible jeers, but his time was an emphatic statement of intent, even with a marginally illegal following wind.
It was faster than Usain Bolt has run all year and suggests he is in shape to go faster than his world-leading personal best of 9.74secs come the business end of the competition.
Bolt's reception, back at the scene of his first triple Olympic triumph, was unsurprisingly in complete contrast as he lapped up the applause, but he could not match his rival's time.
The Jamaican won his heat in 9.96s, albeit into a slight head wind.
Gatlin refused to read too much into the first-round times, saying: "I went out there and ran the first half of my race really well. I feel good.
"Bolt did the same thing in 2012. He raced slower in the first round, picked it up in the semis and crushed it in the final."
Bolt said: "It wasn't as great as I wanted it to be, but I wasn't expecting the first one to be great.
"I wasn't trying to run fast. I wanted to save as much energy as possible. I am in wonderful shape."
Thirty-three-year-old Gatlin's 20-year-old team-mate Trayvon Bromell was the second fastest qualifier in 9.91.
There was mixed news for the Great Britain contingent, though.
Chijindu Ujah looked comfortable as he clocked 10.05 to go through second in his heat, while Richard Kilty, the world and European indoor champion, progressed as a fastest loser in 10.12.
But James Dasaolu was made to pay for a colossal and inexplicable error of judgement.
In the lead metres from the line he looked around and lost all momentum, coming home fourth in his heat in 10.13 to miss out on the semis by one hundredth of a second.