It's every athlete's worst nightmare: your sport's rules change overnight and suddenly decades of training are rendered redundant.
That's precisely the predicament facing Olympian Kate French, who is considering retiring from modern pentathlon as a result of boardroom-level tinkering.
The sport, which combines shooting, fencing, swimming, show jumping and cross-country running, was devised by Baron de Coubertin, who also revived the Olympics in 1896.
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The day-long event is the runt of the Games litter when it comes to TV viewership. In Rio, it was the least-watched in terms of viewer hours, with less than half the audience of the second-lowest sport, trampolining.
In response, the IOC approved an overhaul of the format for Paris 2024. The new 90-minute competition will crunch equestrian into 20 minutes and other disciplines into 15, all staged on the same field.
The drastic changes make the European Super League look like a minor tweak to football's fabric and French, who finished fifth on her Olympic debut in 2016, is fuming.
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"I haven't spoken to anyone who has anything positive to say about it yet," she said.
"I'm not keen on it. Modern pentathlon isn't the most watched or most popular, but I think there are other ways that we could market the current product better, rather than change [it].
"I can't say I fully understand the format. Athletes weren't consulted and I don't think any of the top 36 athletes in the world have tried it.
"The sport will completely change and you're learning again from scratch really. I love the sport as it is already."
French is far from alone, with Russia's Uliana Batashova among those to accuse governing body UIPM of 'killing' the sport.
Men's world champion Valentin Belaud was one of a small group of athletes to speak out in support of the new format.
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He said: "My first thoughts go towards keeping this version and resisting change. But this would be a selfish thought because this could question our place in the Olympic Games."
French, 29, believes other established athletes like Britain's 2018 world champion Jamie Cooke, 30, may also feel cast aside by the changes.
She said: "Before Rio, I thought I would stop after 2016 but I loved the Olympics so much I really wanted to have another go.
"Training would have to be very different and I'm not sure I'm willing to start from scratch. I don't know whether I will be in Paris to see these changes come in.
"Whether they go ahead with the new format could decide whether I carry on after Tokyo and I think that's going to be the same for a lot of older athletes to be honest."
All this comes with French in the form of her life.
In March, the world No.3 set a fencing world record of 31 wins from 35 bouts en route to World Cup gold in Budapest before securing silver in Sofia, Bulgaria the following week.
Having produced her personal best during the pandemic, she will be among the favourites for gold at June's world championships and at the Olympics in Tokyo.
"Breaking world records never crossed my mind for this season,"she said.
"It was all about getting back to competing and building on the good training we could do once things opened up.
"We've got used to competing under the new protocols that will be there in Tokyo and it doesn't make anything more difficult really. We spend all of our time in masks when we're fencing anyway!"
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