* Bolt delivers in the rain to reclaim 100 metres title
* Gatlin takes silver, Carter bronze (Adds details, quotes)
Usain Bolt produced his killer-instinct for vaporising rivals by regaining his world 100 metres crown in the Moscow rain on Sunday, restoring some credibility to a sport tarnished by a plethora of doping scandals.
His victory in 9.77 seconds, holding off American Justin Gatlin (9.85) and fellow Jamaican Nesta Carter (9.95), banished memories of his Daegu false-start and disqualification when he was forced to slope away from a 2011 final he did not get to contest.
Two years on it was less Bolt the showman of Olympic and world record acclaim, more Bolt the serious.
"I wanted to do a better time but was not able to because of the weather," Bolt said. "Not singing in the rain, but running in the rain tonight.
"I'm feeling good, just a little bit tired. I need some rest."
With his world record of 9.58 set at the 2009 Berlin world championships seemingly now a distant memory, Bolt still hammered home the message with each muscle-extending stride that he remains sprint king of the track at 27.
"It was not revenge for Daegu, I just came here to win this title," Bolt added.
"I cannot forget Daegu because all you guys keep reminding me on my false start."
Bolt has been far from his best this season - but his best on the night - the second fastest time of the year after American Tyson Gay's 9.75 in June - was good enough.
As rain fell and thunder clapped around the Luzhniki Stadium, a pensive-looking Bolt mimed taking out an umbrella before the start.
Unlike his embarrassing Daegu downfall, Bolt this time made no mistake out of the blocks and although trailing Gatlin, directly to his left, at halfway, he surged to the front at 60metres.
Gatlin, former world and Olympic champion and twice banned for doping, stayed on his shoulder all the way to the line, followed by Carter and two more Jamaicans Kemar Bailey-Cole and Nickel Ashmeade.
"I feel good if I'd run a perfect race and got beaten I would have been concerned, but I didn't run a perfect race," Gatlin said.
"I got a little over-excited and didn't execute the last 30 metres."
Injured Jamaican Yohan Blake did not defend his title from Daegu while Gay and former world record holder Asafa Powell were not in Moscow after testing positive for a banned substance.
Those failures and positive tests from two-time Olympic 200 metres champion Veronica Campbell-Brown, fellow Jamaican sprinter Sherone Simpson and a host of athletes from Turkey and Russia, have dragged down the reputation of the sport.
Bolt, however, is doing all he can to repair.