Usain Bolt is curious as to who will replace him as the world's fastest man.
He's confident nobody will know at his last major race, at the world athletics championships in August in London.
Bolt was unperturbed when asked on Monday if he was afraid of losing his last race before retirement.
"My coach always finds a way (for me to win)," he said. "I'm not worried."
As for his successor, he was looking forward to the years ahead.
"I'm definitely excited just to see sit and watch and to see who's going to be the next Olympic champion in the 100, 200 meters," he said. "There're a lot of young stars coming up. It's exciting...