Olympic silver medallist Pavlo Tymoshchenko believes the International Modern Pentathlon Union’s (UIPM) 90-minute format proposed for the Paris 2024 Olympics will create "another wave of confusion" and make the sport "even more incomprehensible".
The UIPM Executive Board has recently approved plans to pack all five disciplines into 90 minutes, with an elimination system designed to reduce the length of the competition.
UIPM President Klaus Schormann claims the changes can have a "transformative effect" on the profile and popularity of the sport which was first introduced into the Olympic Games in 1912.
But the 90-minute format is facing criticism from some competitors, with Russian Uliana Batashova notably accusing UIPM of deciding to "kill our sport".
Ukraine’s Tymoshchenko, who clinched silver at Rio 2016, has also spoken out on social media although accepted changes are "needed".
The new format would see the equestrian leg last 20 minutes, followed by 15 minutes of fencing, 10 minutes of swimming and 15 minutes for the laser run - with breaks accounted for between events.
A total of 36 athletes would compete in each competition, with only 12 advancing to the final.
Tymoshchenko said reducing the number of competitors had "several attractive qualities" as well as "several drawbacks".
The 34-year-old also raised question marks over the proposal for the laser run, which would see athletes go around a 600-metre circuit four times.
"Reducing the distance to 2,400 metres as a standalone change will cause an imbalance," Tymoshchenko said.
"Instead of the expected improvement, pentathlon will become even more incomprehensible, especially for the general public.
"There will be another wave of confusion, which will lead to another decline in the quality of pentathlon, the loss of generations of athletes, coaches and specialists.
"Of course, the modern pentathlon should develop, but only if the changes will be beneficial for the sport.
"The new format is not clear and too broad.
"From the first sight, there are obvious difficulties in understanding and commenting on the competition, difficulties and new requirements for training the athletes, the potential increase of the existing infrastructure problems as well as much more."
Tymoshchenko has suggested holding the event over two days rather than one, with a 100-minute format that features an 800m laser run circuit.
"I would appreciate an approach where UIPM will not insist on the deep changes to the existing rules, but will work on the development of a series of third-party competitions," he added.
"Such competitions will allow to try out various options for tournaments with well-known and highly trained athletes, as well as to use the marketing appeal of the 12-person finals format in order to develop and improve our sport."
UIPM - World Pentathlon, Modern pentathlon athletes committee, Olympic For almost 30 years modern pentathlon has been...Posted by Pavel Tymoshchenko on Sunday, 8 November 2020
Tymoshchenko has also called on the UIPM to supply more information on the changes including how much money could be saved and how many more viewers could be attracted.
"I understand that the world is constantly changing, and some changes are needed to be done," said Tymoshchenko.
"I also understand the interests of the International Olympic Committee (IOC) if the IOC is the initiator of this reform.
"It would be beneficial to accompany each proposal with the measurable targets."
Shiny Fang, secretary general of UIPM, acknowledged athletes' concerns and insisted comminution would be "key" as the format is refined over the next two years.
"We are very aware of the concerns raised by some athletes about the new modern pentathlon format for the Paris 2024 Olympic Games, especially before the video conference call we arranged with elite athletes in conjunction with the UIPM Athletes Committee on November 11," Fang said.
"We were happy to have the opportunity to address many of the athletes’ concerns and answer their questions during that call.
"Transition can create challenges and we believe it’s vital that the new Olympic Games format keeps all five essential disciplines, as envisaged by our founder Baron Pierre de Coubertin.
"We also need to shape the presentation of Modern Pentathlon to be more fan-friendly and media-friendly, to showcase the whole sport in a shorter time without losing audiences through long breaks.
"Communication is vital and we will continue to engage with all stakeholders as this new format is refined in 2021 and 2022, through further testing and consultation."
The UIPM has previously claimed it received "positive feedback" following test events in Budapest in Hungary and Cairo in Egypt.
The IOC Executive Board is expected to decide on December 7 whether to approve the new format as well as UIPM’s other proposal to add the mixed relay as an event for Paris 2024.
If approved, the number of modern pentathlon gold medals on offer would jump from two at Tokyo 2020 to three at Paris 2024.