Austin (AFP) – Retired sprint king Usain Bolt has vowed to pursue his dream of playing professional football but admits he will not “embarrass” himself if his goal is out of reach.

The Jamaican track and field superstar, who retired from athletics after August’s World Championships, has long spoken of trying his hand at soccer and has been invited to train with Bundesliga side Borussia Dortmund.

Bolt, the 100m and 200m world record holder and eight-time Olympic champion, insists he is serious about his football dream despite scepticism that at, 31, his advanced age will count against him.

“It’s a personal goal, I don’t care what people really think about it,” Bolt told reporters on the sidelines of the Formula One Grand Prix in Austin on Sunday.

“I am not going to lie to myself, if I feel I can’t do it, I am going to say ‘Forget this’. I am not going to embarrass myself.

“It’s a dream, it’s another chapter of my life that I really want to do. If you have a dream or something you really want to do, you want try to see where it could go.”

Bolt has had a longstanding invitation to train with Dortmund, an arrangement facilitated by his long-time sponsors Puma.

– Open invitation –

However the Jamaican has not taken advantage of the Bundesliga side’s offer yet because of a niggling hamstring problem.

“My hamstring is just keeping back right now, in two weeks I can train again and get back to some shape, then I can really explore that situation,” Bolt said.

“They said the invitation is always open, so it is all about me getting over my injury and into shape. Then I can explore it and do the trials and see what level I am at.

“For me it’s just to try to see if I really can be one of the best, anything I am doing, I’ll try to do it at my best.”

Bolt however admits that he is not optimistic about being granted a similar opportunity with the club he supports, Premier League giants Manchester United.

“It would be difficult to convince (Jose) Mourinho, but we never know, it’s something I said to Alex Ferguson the other day when I was there,” he joked.

Bolt meanwhile said he hoped to find a role with the International Association of Athletics Federations (IAAF) after exploring options for his football career.

“I am waiting to see if my football career is going anywhere, but I definitely want to work with IAAF, in ways to promote the sport, to keep the sport at the level which I left,” he said. “I want to use my name to promote our sport, like an ambassador role.”

Football aspirations aside, Bolt said he is enjoying being freed of his gruelling training regime.

“I am not missing training, not one bit — that’s one thing I know I wouldn’t miss,” Bolt laughed.

“I miss working with coach (Glen) Mills, I try to talk him as much as possible, to talk to him, to have some laughs,” he said.

“I know when the competition starts, and I start to see everybody, the track meets, definitely I’ll miss that.”