Kammala jumla mai zuwa: A cikin 1994, a Hengelo Dennis de Vreugt ya lashe gasar zakarun matasa ta Netherlands a cikin rukunin shekaru U16. A cikin 1998, ya lashe Gasar Zakarun Turai ta Matasa a cikin rukunin shekaru U18, amma a shekara mai zuwa Dennis de Vreugt ya zama na farko a Gasar Zakarun Turai ta Matasa a cikin rukunin shekaru U20. A shekara ta 2000, a Istanbul an hada shi a cikin tawagar 'yan kasar Holland a
34th Chess Olympiad a matsayin mai ajiyar ajiya na biyu, amma bai buga kowane ɓangare ba. A shekara ta 2002, a Hoogeveen gasar zakarun kasa da kasa Dennis de Vreugt ya raba na biyu a bayan mai nasara Evgeny Alekseev. A cikin 2003, a Santo Domingo tare da Bartosz Soćko, Vadim Milov, Alexander Moiseenko da Liviu-Dieter Nisipeanu sun ɗauki matsayi na farko a gasar zakarun duniya.