"Am I impressed with Armand?" said the US Army Reserve officer from Mississippi with a thoughtful expression. "I’ve been following him for probably the last decade. I’m one of his biggest fans. The whole thing about Mondo is everyone saw him coming. I don’t know if he was ever a dark horse."

With his first Diamond League victory earned, and  his personal best ticking up to the heady height of 5.93 metres this season -breaking his own world junior record for the umpteenth time - it’s fair to say that the young man whom everyone saw coming has now arrived.

Sure, he’s a rival. But you feel as if, for some of his fellow vaulters, the inexorably talented Duplantis - who will seek to win his first major senior medal, perhaps even a golden one, at the European Athletics Championships due to start in Berlin on Tuesday (August 7) - is also a project. Loved and feared at the same time.

Kendricks, of course, doesn’t get a say in where the medals go in this particular Championship. He’ll have to chomp at the bit until the IAAF Diamond League final at the end of August.

And while there are several talented contenders for gold in Berlin, including two former world champions in Raphael Holzdeppe of Germany and Pawel  Wojciechowski of Poland, plus the latter’s compatriot Piotr Lisek, the world silver medallist, the two outstanding talents on view will be Duplantis, who completed his set of junior medals in Tampere last month by winning the world under-20 title, and France’s 31-year-old London 2012 champion, world record holder and current world indoor champion Renaud Laviillenie, who will be seeking a fourth European title having won his first in 2010.

The potential narrative in this impending competition is a classic one - an athlete who’s done it all versus an athlete who has it all in his reach.

On the evening before the main IAAF Diamond League meeting in Lausanne last month the world’s top vaulters were involved in a non-scoring, but significant competition in a temporary venue on the shores of Lake Leman.

The raised runway was set up within the Fan Zone which, 24 hours earlier, had held thousands of hopeful, and ultimately resigned Swiss football supporters following their nation’s World Cup progress.

The format – with spectators nosing up to within a yard or two of the runway, and an MC randomly accompanying the vaulters back up the track after their efforts and inviting them to share their thoughts - is becoming increasingly popular, although it was relatively new for young Duplantis.

For the spectator it affords a fascinating close-up of a competition in progress, and it is possible to note nuances of the action that would normally be missed in the vastness of a stadium - vaulters discussing between each other where to set their take-off marks, the obvious general appreciation on behalf of the exuberant Wojciechowski’s achievement in clearing a season’s best of 5.84m, the general chat given out by the endlessly chirpy Kendricks, generally acknowledged and reciprocated, although on one occasion blanked by Lavillenie, who was preparing to set off down the runway, and who eventually won with a clearance of 5.91m.

Duplantis, for all his youth, was an integral part of the group dynamic. At one point, although his face remained impassive, he said something that caused two of his companions to burst out laughing.

He’s a smart cookie. Immediately after the competition Duplantis, his eyes large and intense, answered my questions with precision, even taking control of the recording dictaphone when noise levels rose around him. But he was clearly conducting an internal review of the events that had just passed - it was like talking to someone who was composing a symphony in their head at the same time.

"You can never know everything, so there are so many things to learn every day," he said. "Every day is a big learning experience, especially today. It was a little tough to get used to the runway. I mean, Renaud and Pawel did a great job with it and it was good that they got the step in and put on a show for the crowd.

"I’ve not had an extreme amount of experience of this kind of set up, but I know I have to jump on it more in the future so today was a great learning experience.

"But I know that I’m still in good form, I felt great running, I feel healthy and strong so I know I’ll jump high in the future."

IInterviewed by the MC, Duplantis expressed similar sentiments, and when invited to compliment the event’s senior high achiever, mentioned that he had recently spent 10 days training with Lavillenie at his base in Clermont-Ferrand, and adding, again impassively, that the Frenchman had had "a good hair day".

It was an interesting comment, mixing respect and a challenging levity.

I was put in mind of the moment described by quadruple Olympic rowing champion Matt Pinsent in his illuminating 2004 autobiography, A Lifetime in a Race when he describes his first experimental outing as a 19-year-old in a pair with the revered then double Olympic champion Steve Redgrave, in company with whom he would go on to collect his first three golds at the Games.

"By the end of the session I was getting cocky," Pinsent writes. " 'Let’s row 10 strokes and see who pulls the other one round,' I suggested…

"After about three strokes it was clear I was not going to win this one. The boat was carving round to me, and no matter what I did I couldn’t stop it. Stunned and disappointed, I called a halt and it was only when he turned round that I realised he was using all his strength and the rudder to move the boat in a tight semicircle.

"From then on the tone was set between us. We competed against one another in everything. Only when we raced did we join forces against the rest."

Lavillenie and Duplantis don’t have the opportunity to combine their talents in the manner of rowers - although you imagine they would make a good job of it if they could.

But they do seem to combine the edgy respect and competitiveness that will make the forthcoming men’s pole vault at the Berlin European Championships an unmissable sporting spectacle.