Olympic champion Usain Bolt could lower his 100 metres world record to 9.4 seconds if in shape and the rain clouds stay away from London, International Amateur Athletics Federation (IAAF) president Lamine Diack said.
"Anything is possible. I think if Usain Bolt is in shape possibly we will see 9.40-something (seconds) in the 100m," Diack told reporters on Tuesday.
Bolt's record-breaking 100m win in 9.69 stunned the world four years ago at the Beijing Olympic Games only for the 27-year-old Jamaican to better his time to 9.58 in Berlin at the world championships a year later. Bolt also holds the world record in the 200m set at 19.19 set in 2009 in Berlin as well.
In London, though, he has a new challenge from a familiar face in training partner and compatriot Yohan Blake, who beat Bolt in the 100m and 200m at the Jamaican trials and is the fastest man over the first distance this year.
"I am convinced that we are going to have extraordinary events and spectacles," Diack said. "For me the Games begin on the 3rd (when track and field starts)."
American great Michael Johnson said earlier this month that he too believed Bolt is capable of running 9.40 seconds if he can improve his starting position in races.
Diack also confirmed that the Federation would stick with its one false start rule, having recently clarified that athletes can twitch or flinch in the starting blocks without being disqualified as long as their hands do not leave the ground or their feet leave the blocks.
Bolt famously false started in the final of last year's world championship 100 metres, ending his chances of defending his title in South Korea.
The IAAF added that the dates for the world championships in London, 2017, had been approved as August 5-13.