If Greene is successful in adding an Olympic title to his list of accolades next year he would become just the fifth British athlete alongside Linford Christie, Daley Thompson, Jonathan Edwards and Sally Gunnell to win all athletics' major medals - an incredible feat for a man who only began to take an atheltics career seriously at University.
Greene explained: "I came to the sport very late, there's a lot of people who had achieved so many things at 16 or 17, like world junior titles, European titles things like that,"
"A lot of people saw me as this guy who was ok, a decent standard but I don't think they thought I could become one of the best in the UK.
"I worked part time in McDonalds and I worked in Next. The reason I left Next is that they gave me no time off for the Commonwealth Games.
"I had to try and earn some extra cash because I was only at University and I wasn't making much from athletics."
For Greene, winning gold at the Athletics World Championships, was a matter of personal belief.
"I knew that up until that final in Daegu I'd done everything in my power to be in the best shape I could be in," said Greene.
"I fully believed I could win that final because I'd trained so hard for it and I just wanted to do myself justice. I thought I've got to make it happen.
"When I look at my medal now, I feel a lot of pride."
Greene says it is an "honour" to be compared to fellow Welsh hurdler and three-time world champion Colin Jackson - putting his continued success over the past few years down to his Team Bath coach, Malcolm Arnold, who also worked with Jackson during his illustrious career.
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