Caster Semenya is to run the 800m and 1500m on successive days at the Athletics World Cup in London this week.
The cup, however, is without many other top athletes.
World 100m champion Justin Gatlin, world indoor 60m record holder Christian Coleman, Diamond League 100m leader Ronnie Baker and sprint man of the hour Noah Lyles - the cream of US sprinting - are skipping the inaugural event.
Also absent are Britain's finest, including national record holders Dina Asher-Smith (women's 100m) and Laura Muir (women's 1500m) and top sprinters Zharnel Hughes and Reece Prescod.
Even pole-vault world record holder Renaud Lavillenie will be missing from the French team in the eight-nation competition that matches men's and women's teams from the US, Britain, France, Germany, China, Jamaica, Poland and South Africa.
They will compete on Saturday and Sunday in running events through 1500m and all field events for R27-million in prize money with one entry per nation for each event.
Despite the absentees, UK Athletics chief executive Niels de Vos said he was not concerned.
"We always knew that a couple of athletes wouldn't be able to make it because they had signed contracts for Diamond League events," he told the Guardian. "But the overall quality is going to be astonishing."
De Vos also labelled as "complete nonsense" talk of sluggish ticket sales.
WORLD BEST PERFORMANCES
"It's not going to be Olympic standards with people hanging from the rafters, but it's pushing 30,000 for the Saturday and a little less on the Sunday," he said.
Headliners include double Olympic sprint gold medallist Elaine Thompson, who will run the 100m and 200m for Jamaica; South African Olympic and world 800m champion Semenya, who will double up in her speciality and the 1500m; and Polish women's hammer-throw world record holder Anita Wlodarczyk.
Wlodarczyk, Semenya (800m) and Clarence Munyai (200m), Americans Sam Kendricks (pole vault) and DeAnna Price (women's hammer throw), Poland's Wojciech Nowicki (hammer throw), Jamaica's Fedrick Dacres (discus) and Britain's Lorraine Ugen (long jump) all have the best performances in the world this year.
Athletics' global governing body, the IAAF, also offered its support."We need to innovate in the sport and continue to encourage and support individual federations to do this," the IAAF told Reuters. "Not everything that is trialled will work, but we should not be afraid to try.
"We are quite sure all the athletes attending are looking forward to the event and being part of something new."
But for a number of athletes and their managers the importance of the meeting is questionable.
"It's just a choice of preparing for another non-significant event with three tough years of world championships, Olympics and world championships (ahead)," Gatlin agent Renaldo Nehemiah told Reuters in explaining why the sprinter skipped the US championships/World Cup qualifier.
"Athletes need a break," added the former 110m hurdles world record holder. "Maybe it (the Athletics World Cup) should be for emerging athletes not ranked in the 10-15 and higher."
Others are concerned that another event is being added to an already crowded global calendar.
The Rabat Diamond League meeting with Lyles, Coleman, Baker and Prescod comes a day before the World Athletics Cup, the Monaco Diamond League is days later, and the two-day London Diamond League event follows at the July 21-22 weekend.
There is also a question for some of long-term financial gain.
"It is more lucrative to follow the Diamond League path where they (athletes) get bonuses and qualify for the final and stand a chance to get a bye for the world championships and earn even more money," said one of the sport's key international followers.
Members of the overall winning Athletics World Cup team will receive R135,000 with others earning amounts related to their team's finish.
A platinum trophy organisers are calling the most valuable sporting trophy ever made also will go to the winning team.
But even with a full slate of key competitors, the event would be challenged for fans' interest.
The same weekend as the Athletics World Cup there will be competition from the Tour de France, the Wimbledon singles finals and soccer's World Cup final in Moscow...