The Belgian, who turned 19 in February, finished safely among the main GC group on the final stage, a 134km race over the Col de l'Iseran to Villaroger. He won the race by 1:23 ahead of Norwegian Johannes Staune-Mittet and two minutes ahead of Germany's Michael Hessmann, both of whom ride in the Jumbo-Visma setup.
Uijtdebroeks' success was built on the back of two stage wins, with a dominant victory on stage 7's summit finish at Saint François-Longchamp a key part of his overall triumph. He also won stage 8 to La Toussuire and his Belgian team took second in the mid-race team time trial.
"From a young age I dreamed of wearing the yellow jersey in the Tour de France one day," Uijtdebroeks said after his win. "To take the yellow jersey and to win it now is a dream. I don't know yet what the future will bring but I am very happy that I won here."
Uijtdebroeks, who turned pro straight from the juniors with a big reputation and plenty of wins to his name, is only the fourth man from Belgium to win the race in 58 editions, with Eddy Schepers, Johan Bruyneel, and Jan Bakelants having won in the past.
The race is a key signifier to pro success, especially in the Grand Tours, with Tadej Pogačar, Egan Bernal, Miguel Ángel López, and Nairo Quintana among winners in recent years.
Uijtdebroeks said that the Jumbo-Visma pair had teamed up to try to attack him on Sunday's final stage, going on the offensive on the way down the Iseran. However, he and his Belgian teammates were able to control the situation and deliver the overall victory.
"It was a tough stage," he said. "We had the yellow jersey, and a lead of 1:23 is a lot on one hand. But on the other hand, you can lose that lead very quickly. The guys on the team were a little tired, but they gave everything to control the race. We had Alec Segaert in the breakaway in case something happened. Everyone was very anxious, and they really went to the limit.
"On the descent of the Col de l'Iseran the riders of Jumbo-Visma – even though they were from different countries – tried to attack me. William Junior Lecerf did a really great job and I have to thank him. He was in front all the time and he and I reacted to the attacks.
"It's incredible that I can win this race. It was already a dream to come, but to win... It's a dream."
Uijtdebroeks said he wouldn't be racing the Road World Championships in Australia at the end of the season, but will instead look towards the Italian autumn Classics.
"Normally I won't go to the World Championships," he said. "I am going to recover a bit first. Then I'll go on a training camp to prepare for the last part of the season with Bora-Hansgrohe, and the Italian races in October. I want to prepare well, but first I'm going to enjoy this because it's really great."
Uijtdebroeks also won the KOM title and the young rider's jersey, while Casper Van Uden (Netherlands) won the points jersey. Lorenzo Milesi won the final stage, Italy's first stage win at the Tour de l'Avenir since 2018.
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