Kammala jumla mai zuwa: Gytis Masiulis ya fara zama matashi na farko ga Lithuania a gasar FIBA ta Turai a karkashin 16 a Latvia a shekarar 2014. Ya lashe lambar tagulla tare da Lithuania a cikin 2015 FIBA Turai Under-18 Championship. Shekara guda bayan haka, ya lashe lambar azurfa a gasar cin kofin FIBA ta Turai ta 2016 a Turkiyya. A cikin 2017, Masiulis ya wakilci Lithuania a
2017 FIBA Under-19 Kwallon Kwando na Duniya.