American Jeremy Wariner believes he can break Michael Johnson's 400m world record at the World Championships, which start in Osaka on Saturday.
Wariner set a new personal best earlier this month
Wariner has been following the training programme Johnson used before running the current record time of 43.18 seconds in Seville eight years ago.
"The coach pulled out some of Michael's work-outs and the average times are about the same," said the 23-year-old.
"I am on pace, training-wise, to go for the record, if we go for it."
Olympic champion Wariner clocked up a personal best 43.50 seconds in Stockholm earlier this month and is confident of retaining his world title.
"If I run like I did in Stockholm, they are not going to beat me," he said.
"My first 200m in Stockholm was faster than Michael's in his record. It is between 200 and 300 where I have to work on."
But Wariner warned: "I'm not going to go after it (the record). If it comes, it comes. I am going for victory and if I win, maybe the record will come as well.
"There are a lot of races ahead of me - if not (in Osaka) then there is the Olympics next year and a lot of other meetings."
The men's 400m heats in Osaka are on 28 August with the final three days later.