The 33-year-old Martinborough architect takes confidence, however, from the fact that she bettered Molchanova's record at the national indoor championships in Porirua in August but with no international A judge there it did not count.
That won't happen here as, thanks to generous support from local sponsors, a judge with the appropriate qualifications arrives in Masterton from Los Angeles today to oversee proceedings and he will be joined by several of this country's leading freediving officials as well.
Also pleasing Nevatt has been her form at recent training sessions at the Masterton pool.
She admits, for instance, to getting "very close" to Malchanova's distance last week and has also managed personal bests on the stretch cords which make up the bulk of her out-of-water preparation.
"Everything has been going well ... I know I can do it," she said. "There are a few nerves about but they will go, it should be all good."
Just how many attempts Nevatt will make at the world record remains to be seen. Even if she does the business at tomorrow morning's session, which will run from 10.15am to 11am, she will still try to go further at some of the other sessions planned for Saturday (10.15am to noon and 4.45pm to 6pm), Sunday (9.45am to 11.30pm), Tuesday (10.15am to 11am) and Wednesday (10.15am to 11am). Monday is a rest day.
There is a strong chance, too, that Wellingtonian Dave Mullins will attend the Saturday and Sunday sessions and attempt to beat his own men's word record in dynamic without fins of 218m which he set in 2010. Mullins has gone 232m unofficially so, like Nevatt, he is well placed to set a new mark at the Masterton meet.
The weekend programme also allows for a have a go public session between 11.15am and noon on Sunday at which the likes of Nevatt and Mullins will give expert coaching to any aspiring freedivers.
Those participating there will need to have their parents on hand if they are under 18 years of age.