Later in 2000, Duno made her American Le Mans Series debut; she was the first woman to finish in a class podium on this championship. She made her 24 Hours of Daytona debut the next year and her 24 Hours of Le Mans debut a year later.
Duno's racing career progressed with notable achievements in 2000, including her first American Le Mans Series podium finish as a woman. She followed this success with appearances at the 24 Hours of Daytona and 24 Hours of Le Mans.