"He is a great role model for all of us young riders," Hvastija told AFP after finishing runner-up in the event organised every June in Komenda, just outside the capital Ljubljana, for riders aged eight to 19 years.
With Pogacar eyeing a third Tour de France title to add to last month's first Giro d'Italia victory, his success -- with that of his compatriots Primoz Roglic and Matej Mohoric -- has led to a cycling boom in the Alpine state of two million.
"Years ago we had barely 50 kids in the juvenile team, now we have more than 200," Pogacar's father, Mirko, who helps organise the Pogi Cup, told AFP.
He believes Slovenia establishing itself on the biking map is a "fairytale that I don't think we could see again in the next fifty years".
As Pogacar, the Tour de France winner in 2020 and 2021 and runner-up for the last two years, aims to become the first rider in 26 years to win the Tour and the Giro in the same season, Mirko Pogacar remembers his son as an "unstoppable and skillful" youngster.
He recalls how Tadej and his older brother Tilen would use every occasion to practice in the saddle.
Once they spotted a mound of soil in a neighbour's yard. "They made a (biking) path across it and spent the day riding over it up and down," smiled Mirko Pogacar.
At the age of eight, when Tilen joined the Rog cycling club outside Ljubljana, Tadej wanted to join too but there was no bike small enough for him, and he had to wait months until one was found for him.
'Still ground for more'
Mirko said his son -- whose "first and ultimate great love" is cycling -- was "always among the shortest kids" and so had to fight harder to compete.
"Once he grew up, he became much better than those that had got big earlier," he said.
By now, Pogacar -- a member of the UAE Team Emirates -- leads the UCI World ranking. The 25-year-old won bronze at the covid-delayed Tokyo Olympics.
Pogacar senior said his son "sets himself goals to achieve in cycling and that keeps him going".
"To become a champion, all parts of that puzzle have to fit, if only one is missing, the picture is not right," he said.
"Tadej is only now entering the best riding years, that is between 25 and 27, so he might have quite some years more."
Pogacar's first coach Miha Koncilija, believes the Slovenian rider, known as 'Pogi', is "at a peak".
"But, knowing him, I believe there is still room for more," Koncilija told AFP just days before the 2024 Tour de France this weekend.
"He simply enjoys riding, enjoys training and beating his rivals."
Pogacar is also expected to join Slovenia's cycling team at the Paris Olympics next month and the Cycling World Championship, scheduled for September in Switzerland.
At the end of the Giro Pogacar said "we've checked one of the boxes, two or three more remain for this season".
Koncilija said Pogacar was coping well with his fame.
"Being the best rider in the world is not easy, that brings a lot of pressure with it, but besides that he stops to talk to his fans, give autographs and stays motivated," he said.
The Tour de France gets underway in Florence, Italy on Saturday and finishes in Nice, France on July 21.
