In the searing Georgia sun, American Justin Gatlin works alone on resurrecting a sprinting career cast into limbo by a four-year doping ban.

"It will almost be a half decade," the former world and Olympic 100 metres champion said of his last competitive race in 2006.

Gatlin, though, has never contemplated quitting.

In an athletics world where he once was king but where Usain Bolt now rules, the 28-year-old will regain his eligibility on Sunday and attempt a successful sprinting comeback.

"It is in my heart," Gatlin said. "This is what I do. I feel I owe it to my fans and friends to show them I can still do it."

A 2006 positive test for the male sex hormone testosterone and its precursors at a 2006 Kansas relay meeting and a subsequent four-year ban temporarily wiped out his career.

"Denial, anger, sadness, a little bit of depression, embarrassment set in," said Gatlin, who always denied knowingly taking performance enhancing drugs. "Now I am coming to a point where I am more calm, more mellow."

A young son, Jace Alexander Gatlin, born two months ago, has helped give him a better understanding of life.

"Good, bad, indifferent, guilty or not, I have served my time," the 2004 Olympic 100 metres champion said. "I just want to come back and be able to run; to be able to compete like anybody else."

While speedy times by Bolt, American record holder Tyson Gay and others have shrunk Gatlin's overall world standing, the long suspension may have been lengthened his career.

"Having a longer shelf life is (because) I have been sitting on the shelf," Gatlin said.

How much dust has gathered, the world may discover next month.

If negotiations are successful, Gatlin will make his return in a small meeting in Rakvere, Estonia on August 3.

"He's welcome," meeting manager Taavi Espert said. "If we find the sponsors to pay for the flight ticket, he will be in Estonia."

Lining up other places to run in Europe may not be so easy.

The continent's top meeting promoters have refused athletes like Britain's Dwain Chambers and Gatlin who have served major doping suspensions because of negative publicity they bring.

"No," said Rajne Soderberg, the Stockholm Diamond League organiser and president of Euro Meetings Track and Field organisation, replied when asked whether he would ever invite Gatlin.

US Anti-Doping Agency chief executive officer Travis Tygart would prefer to let athletes compete freely once they have served their suspensions.

LONDON BOUND?

"An athlete who has served his/her period of ineligibility should be fully reinstated to compete again like any other athlete subject to the WADA (World Anti-Doping Agency) code," Tygart said in a statement.

US officials agree.

"He is free to compete in any US, world or Olympic championships for which he would qualify," said USA Track and Field (USATF) CEO Doug Logan.

An International Olympic Committee rule that requires an athlete with a long doping ban to sit out the next Games does not apply to Gatlin because he was sanctioned before the policy was passed, a spokeswoman said.

This season could be the first step toward London, Seagrave said.

"It would be victorious if we could get him a few races under his belt and have him run in the 10.0s and then the sub 10s," said the veteran sprint coach.

"I don't think he has any illusions he is going to walk on the track and run 9.5," Seagrave added in a reference to Bolt's 100 metres world record of 9.58.

But Gatlin, whose lifetime best is 9.85 seconds, said he hoped eventually to challenge Gay (9.69) and Jamaican former record holder Asafa Powell (9.72).

"I think I have enough time from this point on, going into next year to gain the consistent speed that I need to go out there and medal," he said of the 2011 world championships and 2012 Olympics.

But can he beat sprinting's big three?

"I don't know," said Gatlin. "I guess it is time to see."