Modern Pentathlon's future in the Olympics is hanging by a thread as the International Olympic Committee confirmed the guaranteed sports for the 2028 Los Angeles Games.

Surfing, sport climbing and skateboarding - which all made successful debuts in Tokyo this summer - will be part of the programme in California, pending a rubber stamp by the IOC's full membership.

But governance issues with boxing and weightlifting mean both have been placed on a watch list and told to quickly sharpen their acts, IOC president Thomas Bach labelling them 'problem children'.

Modern pentathlon was the brainchild of Pierre de Coubertin, the founder of the modern Olympic movement, who wanted a contest to simulate the experience of a 19th-century cavalry soldier behind enemy lines, ride an unfamiliar horse, fight enemies with pistol and sword then swim and run to return to their comrades.

However, it has long been fighting desperately for relevance in the ever-evolving five-ringed circus, where its involvement dates back to 1912.

It consistently ranks bottom for TV audiences and internal measurements for social engagement, metrics so important to the youth-obsessed IOC.

And the matter got worse in Tokyo as Germany's Annika Schleu, who had been in the women's gold-medal position before the showjumping, was seen in tears after her ride, Saint Boy, refused to jump over the obstacles, her coach Kim Raisner punching the horse in disgust before being sent home from the Games in disgrace.

Embattled modern pentathlon (UIPM) president Klaus Schormann forced through changes at a recent bad-tempered Congress to replace riding with another unknown discipline, incensing athletes including Team GB's Tokyo champions Kate French and Joe Choong, the latter slamming his 28-year stewardship of the sport.

However, the IOC - who are privately fuming about how the situation has been handled - are refusing to green light the sport's involvement until they have more information about its new-look, a move one influential insider dubbed: 'the beginning of the end for pentathlon'.

"Modern Pentathlon must finalise its proposal for the replacement of horse riding and demonstrate a significant reduction in cost and complexity and show improvements in safety, accessibility, universality and appeal for youth," said Bach.

Just 28 nations sent athletes to Tokyo and the IOC are riled by the sport's lacklustre attempts to increase its global appeal, the UIPM claiming the expense of horse riding, a charge that is disputed by athlete campaign group Pentathlon United, is the sole cause of this.

"The situation with modern pentathlon is very different to boxing and weightlifting," added IOC sports director Kit McConnell. "The UIPM went through a review and confirmed horse riding will not be part of the programme for LA, they are going through a process of looking at alternative options.

"They felt horse riding created cost and complexity challenges in different countries for people to access modern pentathlon. They felt they needed to make the sport more accessible and attract a wider audience and we understand the motivation of that step.

"They'll be testing alternatives and finalising a proposal later next year. It's a critical element that they reduce cost and complexity. Once we see what they've proposed we can assess the situation and make a decision about that in 2023. The athletes need to be a central part of that process."