Melbourne: The fastest man in the world, Usain Bolt, did not completely brush away suggestions that he might take part in the 2018 Commonwealth Games, here on Sunday.

Bolt was in Melbourne tonight to attend the Spring Racing Carnival. After thanking his fans before leaving Australia, he said the carnival was an unique experience.

Bolt had earlier said he would be happy to make Australia his home if he moved away from Jamaica.

Asked if he would be back in the country for the Commonwealth Games in 2018, he said: "I don't know. I may. It is a thought, but I don't know."

As he prepared to board his flight to London at the Melbourne Airport on Sunday, Bolt said the highlight of his trip was "going to the races".

"I've never experienced a culture like this," he said.

The Jamaican sprinter added: "I always have a good time when I come to Australia."

He also hinted that after conquering the track, he would want to turn his attention to field events in Australia. He may consider tackling the long jump as part of his involvement in the new Nitro Athletics series, to be held in Australia in 2017.

Bolt had been unveiled as the star attraction of the experimental competition, which would see six teams, consisting of 24 athletes each. The meet in February would be held in Melbourne and would be a mix of track and field events, with a hurdles relay among the proposed non-traditional features.

Athletics Australia director John Steffensen, a 4x400 metre silver medal winner at the Athens Olympics in 2004, had announced the concept in a media conference in the presence of Bolt and had tried to tempt the Jamaican superstar to move outside of his comfort zone.

Steffensen said: "So are you trying to tell me if your team says: 'Usain, we need you to do the long jump. Can you do the long jump?' will you do it?"

And Bolt, a nine-time Olympic gold medal winner across the 100m, 200m and 4x100m relay, indicated he might take up the challenge in his capacity as a captain-coach. Bolt would pocket up to $1 million for taking part in Athletics Australia's new-look Nitro Summer series.

"I think I'm at that point in my career where I don't have to stress too much about "if" I want to do long jump, because my coaches don't want me to do it... But now I actually can. So it will be fun to do different things," said Bolt.

Bolt also did not rule out taking part in the Gold Coast Commonwealth Games in 2018.Organisers have been hopeful that Bolt, 30, could be convinced of a grandstand finish to his career when the Games come to the Glitter Strip in 2018, even though he had remained steadfast in his commitment to retiring at the 2017 Athletics World Championships in London.

But, in a television interview during the Oaks Day races at Melbourne's Flemington, where Bolt was a celebrity guest, the Jamaican left open the possibility of remaining in the sport until 2018 to compete on the Gold Coast.

Last month Gold Coast Commonwealth Games chairman Peter Beattie sent Bolt a formal invitation. (Agencies)