Eighteen seconds is all that separated Dane van Niekerk from a place at this year's T20 World Cup on home soil.

She has led teams to glory in the Hundred and the Big Bash and was recognised as one of Wisden's five cricketers of the year in 2022.

None of that mattered, though, as she fell short of Cricket South Africa's (CSA) strict cut-off time of nine minutes and 30 seconds for a two-kilometre run.

"A minimum standards test is indicative of a player's commitment to fitness, to discipline, to the team culture," said Dr Shuaib Manjra, CSA's chief medical officer.

"These are not fitness tests to determine how fit a player is. They're the minimum entry requirements. And they're very generous minimum standards."

Beyond the time trial, players must pass minimum standards tests for strength-to-weight ratio as well as body composition. But it's the time trial that has a zero-tolerance policy.

Last year, the cut-off for the time trial was reduced by 30 seconds in an effort to improve fitness standards across CSA's ecosystem. It was similarly reduced for male players to eight minutes and 30 seconds.

During this time Van Niekerk, 29, was recovering after fracturing an ankle in an accident at home in January. Her last game for her country was in September 2021.

"Players are contractually obligated to meet these standards and we have buy-in from the players and Saca [South African Cricketers' Association]," said Dr Manjra.

There are contingency plans for players who have just returned from an injury, but CSA see Van Niekerk as having had enough time to meet the required minimum standard.

"A player can have multiple attempts to reach the standard," added Dr Manjra. "We don't put a limit on it. But there has to be a cut-off before the squad is announced. We impose the standards rigorously."

There is precedent for this. Sisanda Magala and JJ Smuts have both previously been dropped from the South Africa men's squad for failing to meet minimum fitness standards.

Lizelle Lee, another generational star in the women's side, retired from international cricket last year, claiming that failing a weight test was a "significant factor" in her decision.

"Clearly there is a problem," said Andrew Breetzke, chief executive of Saca.

"The women's team has lost two marquee players in a few months. Does the system need redress? It has to be a priority if these are the outcomes.

"It's gravely disappointing that Dane will not be involved. But we respect that CSA has the prerogative to put in place fitness standards."

This is why CSA could not make an exception for Van Niekerk despite her obvious pedigree.

"What message would that send to the other players who all met the minimum standard?" asked Dr Manjra.

"We're trying to create a particular culture within our teams. The minimum standard is really a distillation of an attitude.

"For years and years we've battled and struggled to give women's cricket in the country professional status. Let's adopt a professional standard.

"The game is changing. There are more competitions - and we encourage all our players to play around the world - and what teams want are explosive players who can bat, bowl and field. If we require a generational change to bring in this new player then so be it.

"Overall, the decision we made was the right one."