Zeno Koen Debast (born 24 October 2003) is a Belgian professional footballer who plays as a centre-back for Primeira Liga club Sporting CP and the Belgium national team.

[4][better source needed] On 11 June 2024, during an interview for Het Laatste Nieuws, Debast confirmed that he had agreed personal terms to join Portuguese side Sporting CP from the 2024–25 season.

[7][8] On 7 August, he made his debut for the club, where he committed two errors, that led to rivals Porto first and second goals in their 4–3 loss in the 2024 Supertaça Cândido de Oliveira.

[9] This resulted in him losing his starting spot, however, on 17 September with regular starter Eduardo Quaresma being sidelined with a knee injury, Debast was entrusted back to the starting eleven, scoring his first goal for the club, and the first goal of his career, by netting a shot from outside the box in Sporting's 2–0 victory over Lille during the inaugural matchday of the newly formatted Champions League league phase.

[10] In September 2022, Debast received his first call-up to the Belgian senior squad for the 2022–23 UEFA Nations League matches against Wales and Netherlands.