During his time at the academy, he played with the Leinster senior team, making his debut in October 2014 against Italian side Zebre Parma.

[8] Van der Flier won the Guinness Rugby Writers of Ireland men's player of the year award for the 2021-22 campaign.

[13] Van Der Flier was born and raised in Wicklow, Ireland, where he began to play rugby.

He is of Dutch descent on his father's side, his grandparents having moved to Ireland from the Netherlands in the 1950s to open a radiator factory.

[16] Van Der Flier is a practicing Christian, and wears the cross drawn on his wrist tape during games.