Born in the Belgian town of Tienen, Vertessen joined PSV Eindhoven as a schoolboy from Westerlo in 2009.
On 2 May 2021, Vertessen scored his first goal for the PSV senior side in a 2–2 draw with SC Heerenveen in Eredivisie play.[1] On 7 August 2021, Vertessen scored in a 4–0 Johan Cruyff Shield win over rivals Ajax, in turn helping to end Ajax's 17 game unbeaten streak.[2]
On 28 January 2023, Vertessen was loaned to Union Saint-Gilloise until the end of the 2022–23 season,[3] while Union were lying second in the Belgian Pro League, and made his debut in Union's 4–0 win over Zulte Waregem on 5 February 2023.[4]
On 1 February 2024, Vertessen signed with Union Berlin in Germany.[5]
International career
Vertessen featured in the Belgium squad for the European Under-17 Championship in 2018, earning a place in the team of the tournament.[6]