De Koning attended Padua College[2] and played junior football for Mt Martha with current teammate Jacob Weitering[3] and St Kilda player Hunter Clark.

[4] De Koning joined TAC Cup club Dandenong Stingrays and kicked nine goals in 2016 as a 17-year-old against the Northern Knights.

[5] He joined the AFL Academy, played 11 TAC Cup games and kicked 17 goals.

[3] In 2018, De Koning extended his contract until 2021,[6] and made his AFL debut in round 22 against the Western Bulldogs at Docklands Stadium.

[3] * denotes rookie listed players (inj) long-term injury