[4][5] Duncan currently competes in the Irish Hockey League, where he represents Monkstown.

[4][1] He made his debut for the Irish U–21 team in 2014 at the EuroHockey Junior Championship II in Lousada.

[6] Since his debut, Duncan has been present at numerous international events.

He has medalled once with the national team, taking home gold at the 2023 edition of the EuroHockey Championship II.

This biographical article relating to an Irish field hockey figure is a stub.