Michael Johnson will try to add the record of the rarely contested 300 metres to the world marks he holds in the 200m and 400m at the biggest meet of the South African calendar tomorrow.
Johnson, who clocked the fourth-fastest 200m time in history - 19.71 sec - in Pietersburg last Saturday, announced yesterday that he would deviate from his original programme and run the 300m instead of the 200 in Pretoria.
"I think it's a great opportunity to perhaps break the world record in the 300. It would be great to be able to do it here in South Africa. The support has been great," he said. "I feel very good after my race last week. I feel like I'm in great shape, so if it's there, I'm going to go for it and hope I can be successful.
The world record is 31.48, set by America's Danny Everett and the Cuban Roberto Hernandez in Spain in September 1990.
"I was at 31.66 at the 300 metre mark in my 400 world record last year. I think that it's possible, I know that I'm capable of doing it, but it's a very difficult record to break," Johnson said. "I've come close. I ran 31.56 in 1994, which was the last time I ran the distance."
Referring to his race strategy, Johnson said it was like "shooting in the dark. The difficulty in running the 300 metres is that you can't take what you did in the last race and apply it to the next race, because my last race was 1994, so it's difficult to gain consistency and work out the mistakes.
"I'll talk to my coach and get his perspective, but I think that the smart approach is to run hard and see what I come up with and try not to hold back too much. It would probably be smart to lean more towards a 200 metre strategy than a 400 metre strategy."
Johnson will complete his competitive programme in South Africa in Cape Town on 31 March, when he will contest the 400m for the first time this year.