The American topped the pile as the event got underway at Fish-mouth Wetlands in the Chinese city, on a new Olympic-certified park terrain skate park. 

Fellow United States skateboarder Minna Moniz Stess qualified in second with Australa's Shanae Collins third best.

All of the top 23 will be joined in tomorrow's semi-final by the finalists from the Vans Park Series Finals stop in Chinese city Suzhou last week.

The final will follow the semi-final tomorrow.

World Skate have hailed the event as a "historic" first step towards Tokyo 2020 Olympic qualification, with both park and street skateboarding due to make their Games debut in the Japanese capital.

Athletes are battling for seeding as skateboarding moves into its Olympic qualification phase on January 1.

An Opening Ceremony was held today before the women took to the course.

"It's a great pleasure to be with you all here in the beautiful city of Nanjing for the first World Skate Park Skateboarding World Championships," said World Skate President Sabatino Aracu.

"This is the first step for park skateboarding on the way to Tokyo 2020 and I would like to thank the Chinese Government, National Sport Minister Li Jianming, the Municipality of Nanjing, the Chinese Federation and Crownboard for the great opportunity to highlight world-class skateboarding here and for the beautiful skate park they have created for this event that will live on as a beacon for skateboarding and for the city of Nanjing."