He had insisted "I am not Mr YOG" when he took his leave of the first Youth Olympic Games in 2010, but others, including his Singaporean IOC colleague Ser Miang Ng chose to pay tribute to his "vision and legacy".

Rogge, by profession a surgeon, was a three-time Olympian sailor and later a senior Belgian sports administrator. He had watched in dismay as successive Games in the late 1970s and 1980s were blighted by political boycott.

As President of the European Olympic Committees, he drove through the establishment of an event for younger athletes. These were originally known as European Youth Olympic Days. The first competition was held in 1991 over three July days in Brussels.

It attracted 2,840 young athletes from 33 countries in 10 sports. It proved a success and was subsequently held every two years. It was known as the European Youth Olympic Festival and encouraged the development of similar regional festivals in other areas.

Rogge was by now an IOC member but remained committed to the idea of youth sports.

In 1998, there had been a World Youth Games in Moscow but when Rogge became IOC President in 2001, he was eventually able to put into practice his dream for a worldwide event under the Olympic umbrella.

After negotiations with television and sponsors and others, he was able to put his proposal to the full IOC membership in 2007 when they gathered in Guatemala.

 As a medical professional, he was concerned by the growth of obesity amongst the younger generation and a lack of willingness to engage in sport.

He had witnessed a decline in participation, the disappearance of playing fields and what he described as "the appeal of multimedia-based activities to the detriment of sport amongst young people".

He outlined a project to establish Games for 14-to-18-year-olds.

"The YOG would be complementary to the Olympic Games with their own identity and would increase the appeal of sport and physical activity at the grassroots level," Rogge said.

"Whilst serving as a steppingstone to the Olympic Games, the YOG would also serve simply to help the athletes who did not make that step to be better human beings."

Although not everyone welcomed the idea, Rogge found wide ranging support for his idea amongst the IOC membership.

Amongst those who spoke in favour was the great Polish athlete Irina Szewinska, who had won the first of her three Olympic gold medals when she was only 18.

"It would be a great promotion of the Olympic ideal and give young athletes the chance to fulfil their dreams," Szewinska said.

The proposal was accepted unanimously by a show of hands and Rogge’s predecessor Juan Antonio Samaranch even suggested that the IOC’s decision to set up the Games was "possibly the most important step it had ever taken".

A postal ballot later Singapore was selected to be the pioneering host of the first Games in 2010.

The Opening Ceremony was held on a floating pontoon on Singapore’s waterfront Marina Bay Sands. Rogge surveyed the 3,600 young athletes who had travelled to take part and encouraged them to "have fun".

Rogge had earlier prescribed that "every effort would be made to protect the physical and psychological health of the young athletes".

A quota system limited the team size from each country to make sure that all were represented.

As well as sport, the young athletes were encouraged to participate in the "Cultural Educational Programme", a programme of activities designed to help the young athletes manage their sport in conjunction with other parts of their lives.

"What we never had was this combination of education, culture and sport," Rogge said. "We thought that bringing the young athletes together to benefit from Olympic values and the education programme gave added value."

Those who had enjoyed a successful Olympic Career were encouraged to return as "Athlete Role Models" (ARM).

Singapore 2010 explained that "athletes will be able to listen and interact with ARM who will share their life experiences on achieving success in both life and sport".

The concept echoed with discussions spearheaded by Rogge at the 2009 IOC Congress in Copenhagen. Concerns were expressed about the influence of the athlete’s entourage.

At the inaugural Games in Singapore and the first Winter Games in Innsbruck held in 2012, Rogge enthusiastically joined the young competitors at the Athletes' Village to offer advice in what became known as a "Chat with the Champions."

This remains a popular element, though by 2020 it had also included sessions with influencers and how to promote an image through social media.

Rogge confessed to a much simpler pathway in his own youth when he visited the sailing venue.

"I am coming to the roots of the sport I loved. If I could have had something like this," he said. "I would have been very happy. I was raised in the very traditional model, youth classes and then, to the Olympic classes."

Singapore, realising that it was unlikely to host an Olympic Games, had thrown its full weight behind the Youth Olympic Games.

The next summer celebration came in Nanjing in 2014 and then the Games were held in Buenos Aires in 2018. The 2026 Games in Dakar Senegal will be the first to be held on the continent of Africa.

All three Youth Olympic Winter Games have so far been held in Europe but that will change in 2024 when Gangwon province hosts the Games in venues largely used for the Pyeongchang 2018 Olympic Winter Games.

The Games have been described as a “laboratory” in more ways than one.

The introduction of 3x3, sport climbing and breaking have paved the way for acceptance at future Olympic Games.

Mixed team events were also included in a wider range of sports than ever before at the Youth Olympics. This prompted some to describe the Games as a "sports laboratory".

In the last month the success of mixed team judo and triathlon at the Tokyo Olympics demonstrated the value of a well-tested pathway for new events.

Over the last few hours, tributes have already hailed Rogge for restoring the IOC’s credibility in the wake of the Salt Lake City bribery scandal.

The Associated Press considered that he "oversaw an era of political and financial stability in the Olympic Movement after its worst ethics scandal and pursued a hard line against doping".

Rogge was elected IOC President at their Moscow session in July 2001. Within two months, had come the attack on the Twin Towers in New York City and a wider international crisis. It fell to him to navigate the successful staging of those Salt Lake City Games in 2002.

He had also inherited the almost fatally stalled 2004 Athens Olympics. That they did go ahead, and that he was eventually able to describe them as "Dream Games" probably speaks volumes for his own behind the scenes leadership.

Yet it was the Youth Olympic Games which clearly had a special place in his heart, a sentiment he admitted at the Singapore Closing Ceremony.

"“I now have 22 Olympic Games under my belt and the YOG is ranked at the very top," he said.

He certainly cut a relaxed figure at any Youth Olympic event he attended.

Perhaps he really was "Mr YOG" after all.