London, Aug 2 (IANS): Jamaica's Usain Bolt said he was pretty confident about his chances in the upcoming IAAF World Championships, which will be his last competition before retiring.

At a press conference here on Tuesday, Bolt, who will run only 100 metres and 4×100 metres relay, said he would not have decided to compete if he were not sure about his chances, reports Efe.

"If I show up at a championships you know I'm fully confident and ready to go" the world record holder in the 100 meters and 200 meters said.

The 30-year-old Bolt said that he was "really looking forward to watching my first major 100m race as a spectator" after hanging up his boots.

Reflecting on his career, Bolt said that he never expected to achieve all of the success he has had and he talked about the most special gold medal he earned.

"I never knew that I am going to achieve records in one championship - all I wanted was to be 200 metre Olympic champion. That is it," Bolt said.

"The proudest moment in my career was winning gold medal as a junior in front of a home crowd. Nothing beats that feeling," he said.