Armand 'Mondo' Duplantis heads up a stellar cast of athletes kicking off the 16th Diamond League season in Xiamen, Fujian province, on Saturday, amid a changing landscape that has seen Michael Johnson launch his Grand Slam Track series.

Petr Stastny, CEO of the Diamond League, insisted that he welcomed competition, but added he thought the 15-meet circuit he oversees was the "backbone" of global athletics, with a record $9.2 million in prize money on offer.

"You will get the most comprehensive coverage of the highest possible level of competition in our sport, in track and field. Great arenas, great big crowds,"Stastny said.

Former US sprint star Johnson is the founder of Grand Slam Track, which debuted in Kingston, Jamaica, earlier this month.

Conceived by Johnson as a way of reinvigorating interest in athletics outside of Olympic years, his four-event series aims to showcase more races between the world's best runners, sprinters and hurdlers. There are no field events.

"We feel strongly that the sport is more than just track, and we will continue growing the sport — not just a part of it," said Stastny. "We see other events and series being established around us, which we are, generally speaking, happy about.