U.S. sprinter Allyson Felix will receive some last-minute tips from a trailblazer as she launches her bid for a unparalleled 200-400 meters double at the world championships, the three-times world 200 meters champion's coach said on Thursday.

Valerie Brisco is coming in, said Bob Kersee of the first woman to win both events at an Olympics in 1984 at Los Angeles.

She will walk Allyson through what she did, Kersee told Reuters in an interview two days before Felix launches her bid.

No woman has accomplished the double at a world championship. Brisco and Frenchwoman Marie-Jose Perec did it at the Olympics with Michael Johnson completing the double at both the Games and world championships.

I do feel like I'm prepared to handle the workload, Felix told reporters in Daegu, South Korea.

Obviously I am in territory that I am not too familiar with, said the 25-year-old Californian.

I am definitely a little nervous and a little anxious, but I think that is what happens when you step up to a challenge and do something you are not so comfortable with.

The nerves are nothing new for Felix.

If I wasn't, it would be weird, she said.

But the challenge is new, especially in the 400, which comes first on the program.

It is not the most pleasant event, said Felix, who has never run the event in a major championship. But as I run it more it becomes easier.

The schedule calls for three consecutive days of 400 meters running, climaxing with the final on Monday.

After two days to recover, Felix will be back for three 200 meters races in two days.

Then, if she is up to the task, she will race in the finals of the 4x100 meters and 4x400 meters relays.

The task is a busy one, but Felix wants to do all four.

Punishing two-a-day workouts in California have prepared her for the challenge even though her times are not the year's fastest.

She ranks but sixth fastest in the 200 and fourth in the 400.

But I think she is ready and excited, said Kersee.

He has backed off the training since they have been in Daegu.

I have been hanging out in my room, watching some TV, and trying to visual the races in my mind, Felix said.

Her performances are always perfect.

I don't lose in my mind, Felix said, hoping to produce the goods on the track in Daegu.