 Pari gbolohun yii: Tadić jẹ ọmọ ẹgbẹ ẹgbẹ agbọn bọọlu afẹsẹgba ti orilẹ-ede Serbia U-18 ti o gba ami ẹyẹ goolu ni 2017 FIBA Europe Under-18 Championship. Lori awọn ere idije meje, o ṣe apapọ awọn ojuami 3,1, awọn rebounds 2,4 ati awọn iranlọwọ 1.3 fun ere kan. O tun ṣe aṣoju ẹgbẹ agbabọọlu orilẹ-ede Serbia ti awọn ọkunrin labẹ ọdun 16 ni 2015 Championship. Lori awọn ere mẹjọ o ṣe apapọ 4.6 awọn aaye, 2.0 rebounds ati 1.9 ṣe iranlọwọ fun ere kan. Tadić je omo egbe Serbia ti o wa labe ogbon odun ti o pari 15th ni : 2019 FIBA U20 European Championship ní Tel Aviv, Israel. Lori awọn ere idije mẹta, o ṣe apapọ 0.7 rebounds ati 1 ṣe iranlọwọ fun ere kan. 