It is, however, a hurdle that Arnold saw coming. At the age of 76 he was already decided upon a change after seeing out his four-year contract with British Athletics, which finished yesterday, thus bringing to a close 42 consecutive years of employment for the national governing body in its various forms.

"The athletes asked if I could stay until the World Championships in 2017, but UKA declined as it didn't fit their new 2020 strategy," Arnold told insidethegames, adding: "I am very happy concluding a career which has lasted since April 1968 - nearly 49 years.

"I coached 60 medallists from the Bath HPC in 18 years at under-20, under-23 and senior level. Over my whole career the count is 87 medals won by athletes I have coached, with three Olympic champions, four world records [Colin Jackson still holds the 60 hurdles indoor world record] and numerous world champions."

However, for a man who established himself by coaching Uganda’s John Akii-Bua to a shock Olympic 400 metres hurdles record in a world record of 47.82sec at Munich in 1972, the track will continue to stretch ahead a little further as he plans to coach two days a week at Bath in the months leading towards this summer’s International Association of Athletics Federations’ (IAAF) World Championships in London.

The wish of the athletes he oversees in this south-western powerhouse of athletics endeavour, including European 2014 400m hurdles champion and Rio 2016 4x400m bronze medallist Eilidh Doyle, will be respected with or without British Athletics funding.

Almost 45 years after guiding Akii-Bua to Uganda’s first Olympic medal, never mind gold medal, Arnold still cannot resist a challenge.

Having spent almost five years building up Ugandan athletics, Arnold returned to England without a job. But he was soon re-engaged with the sport at the top level as he became National Coach for Wales, a post he held for 20 years until he was handed the poisoned chalice of being UK Athletics head coach in 1994. He held the position for three years, enduring a particularly barren spell in terms of medals as the British athletics team failed to earn gold at either the 1996 Olympics in Atlanta or the IAAF World Indoor Championships in Paris the following year.

In the wake of Atlanta 1996 and before funding from the National Lottery, which had started in 1994, had become the huge business it now is, he vented his frustration at the piecemeal nature of financial support for British Athletics.

"One of the problems in this country is that funding comes from so many different sources," he told me in September 1996. 

"The Lottery Fund, the Sports Aid Foundation, the Foundation for Sport and the Arts, the Sports Council, regional sports councils, Eddie Kulukundis, Uncle Tom Cobley and all.

"There are so many bodies giving out relatively small amounts of money to our sport. That means we have to spend an enormous amount of admin time chasing things up. It is no way to run a show."

The prime frustration for Arnold and his British Athletics Federation colleagues at the time was the shelving of their bid for £9.6 million ($11.8 million/€11.2 million) of National Lottery money to train and support athletes over the next five years.

"We don't know if they are going to deliver," Arnold said. "We don't know what our budget will be, which means we can't plan ahead. If people ran their businesses like that they would be sacked. The Government is fiddling while Rome burns. It doesn't matter to them, people sitting in offices, pushing pens and bits of paper around. But for athletes, as each week goes on, it's another opportunity lost."

Arnold has never shied away from expressing himself strongly, whether it be to funding authorities or athletes or, indeed, those whom he deems to be errant members of the media.

After the underwhelming British performance at the 1997 World Indoor Championships, for instance, he commented: "I know this was the World Championships and that the competition is fierce, but I expected more.

"The men's relay team performed very badly indeed. Steve Smith and Dalton Grant in the high jump didn't do what we hoped for and I was disappointed in Sally Gunnell and Phyllis Smith too.

"They under-performed, it's as simple as that. If they had performed at their normal level they could have won medals."

At the 2011 World Championships in Daegu, Britain’s newly installed 400m hurdles champion Dai Greene tried to describe what it was like being coached by Arnold and recalled his treatment of a former charge, Britain’s Athens 2004 4x100m gold medallist Jason Gardener.

"Malcolm installs a really strong character in you as well, as he takes no crap whatsoever,” Greene said. “Before Jason won the World Indoors in 2004, he had torn both his groins, and was struggling to walk. He was umming and ahhing about whether to compete, until Malcolm said: 'Stop f****** around, just go and f****** do it!'”

In the wake of a victory that added a world title to the European and Commonwealth golds he has already amassed, Greene added: "My confidence, it is not unfounded. It comes from knowing I've done the hard work before I get here."

Almost 40 years on, Greene’s confidence echoed that of another Arnold athlete – Akii Bua. His preparation for the 1972 Olympics involved him perfecting a stride pattern which Britain’s defending champion, David Hemery, had sought and abandoned: 13 strides between hurdles in the first half of the race, 14 thereafter. And he was able to lead with either leg.

It also involved him spending the previous winter in gruelling training while wearing a weighted jacket. No wonder this Ugandan police inspector was confident that he could break Hemery’s world record of 48.12, even running 47.8 if need be, which was exactly what he ended up running to claim gold from the inside lane.

Twenty years later Arnold had an Olympic champion he wasn't expecting. It was supposed to be Colin Jackson, by general consensus the finest 110m hurdles talent present at Barcelona 1992. But the gold ended up with the Canadian who had come over to train with Jackson under Arnold – Mark McKoy.

The man Arnold had trained for 10 years had failed; success had gone to the man he had taken on late - despite the whispers of those who disapproved of the Canadian's past, in which he had admitted taking anabolic steroids as part of the group including Ben Johnson that was coached by Charlie Francis.

"Some people had condemned me without having the courage to say anything to my face," Arnold told me at the time. 

"I didn't seek any assurances from Mark when he first came. But I know when athletes are up to something, and he's back on the straight and narrow. In the present system it's very easy to condemn people. Perhaps my ethics are a little more Christian. Forgiveness is an important aspect.

"I didn't know whether to laugh or cry after the finish. There wasn't much to be said right then - just well done to Mark and bad luck to Col."

Meanwhile, Arnold is casting doubtful glances at the future of British Athletics, which he believes has failed to oversee the development of new superstars to replace the likes of Mo Farah and the recently retired Jessica Ennis-Hill.

"We were doing better when we were skint," Arnold said. "I wonder where the next superstars are coming from. If you look at the neglect of development of athletes, the neglect of development of coaches - which is a subject really close to my heart - people are asking if it’s a showbusiness company or something that develops athletes.