SHANGHAI, China (AFP) — Pole vault world record-holder Armand "Mondo" Duplantis admitted to nerves on the eve of the new Diamond League season on Friday as he seeks to extend his extraordinary unbeaten record. The United States (US) born Swede opens his outdoor campaign on Saturday in a loaded field in China that includes Greece's Emmanouil Karalis, who moved to second on the world all-time list in February with a 6.17m clearance in Athens. The competition in Shanghai/Keqiao also includes two-time world champion Sam Kendricks of the US and double World Championship bronze medallist Kurtis Marschall of Australia.