NAIROBI, April 19 (Xinhua) -- Kenyan Olympic 5000m champion Vivian Cheruiyot will keep to her lane against a spirited challenge from defending champion Mary Keitany and Tirunesh Dibaba at the London Marathon on Sunday. Cheruiyot, who will be running her third marathon, says she will run her own race hoping to exploit any weaknesses Keitany and Dibaba may present in a bid to win a second marathon in three attempts.

The 34-year old Kenyan believes she is still a novice in the game and will not stand in the way of the two great women as they seek to break the world record in London.

"I'm still nervous but I learned a lot in London last year and I hope to run well on Sunday. Since Frankfurt, I have had some more tips from other people and I have trained a bit harder than last year. My aim is to set a new personal best," Cheruiyot said on Thursday.

She has no plans, though, to track either Keitany or Dibaba should they cut out at a world record pace.

"No, no, if they're going to run 66 minutes, I can't keep up with that," she said. "Because they're going for the world record, I can't be there with them but I will go at my pace and we'll see what happens to them."

Cheruiyot reckons she is learning fast with her eyes set on adding the 2020 Olympic marathon gold to the 5,000m title she won in Rio.

"The marathon is hard but everything is possible. I think, if you train and train hard it falls in your strides," she said.

Certainly, it is unlikely that either Keitany or Dibaba would be rash enough to discount the pedigree of this four-time world track champion and former world cross country gold medalist.

"After the 5000m in Rio, I decided I would do more track races. Now, I do miss them. I'll be ready to go for the 2020 Olympic Marathon in Tokyo. I think I will be in a position to challenge then," she added.

Sunday will be only her third marathon after she made an impressive debut in London last year, finishing fourth in 2:23:50. She followed that with her first marathon victory in Frankfurt last October.