American 400 metres hurdles legend Ed Moses has confirmed he is returning to running.
The double Olympic gold medallist made the announcement on his 48th birthday at a news conference on Sunday.
Moses' last competition was 15 years ago at the 1988 Olympic final, where he took bronze a year after the end of his unprecedented decade-long winning streak of 122 races.
Moses won world titles in 1983 and 1987, and Olympic gold medals in 1976 and 1984 - but missed out in Moscow in 1980 after the USA boycott.
He held the world record for 16 years until American Kevin Young broke it at the Barcelona Olympics in 1992.
Moses said his first aim is to achieve the time of 50.55 seconds which would qualify him to run in next year's US Olympic trials.
"If it is possible for me to appear at the Olympic trials that would be fantastic as I am an old man," he said.
"In terms of going to Athens, if things happen they happen, but realistically I can't believe it will.
"But just to be there would serve as an inspiration.
"I am in excellent physical condition and my technique is as sound as it was when I was competing full time.
"I can still run my 13-pace stride pattern and I have already started a training programme.
"I believe with the right application, motivation and technique this is something I can achieve."
But Moses said he had no intention of taking on the likes of current world champion Felix Sanchez right away.
"It's not realistic for me to be chasing the likes of Sanchez or the young boys out there who are young enough to be my son," he said.
"I am not interested in running against world-class guys unless I can achieve the qualifying standard."
Moses, who insisted there were no financial motives behind his comeback, is hoping to inspire other people to go for their own goals in life.
He is currently a member of the International Olympic Committee ethics commission and was a member of the athlete's commission for 14 years and the IOC medical commission for six years.