*Club domestic league appearances and goals, correct as of 15:17, 2 November 2024 (UTC) ‡ National team caps and goals, correct as of 24 September 2022
Brittijn was born in Winterswijk, Gelderland, and played youth football for FC Winterswijk, before joining the De Graafschap youth academy in 2014.[2] He progressed through the ranks, and prior to the 2021–22 season, he began training with the first team.[3] In August 2021, he signed his first professional contract with the Doetinchem-based club.[4]
On 10 September 2021, Brittijn made his professional debut, replacing Ted van de Pavert in the 73rd minute of a 3–0 Eerste Divisie loss to Volendam.[5] He scored his first goal two weeks later, on 24 September, against Jong Utrecht. After being subbed in for Hicham Acheffay in the second half, he equalised after receiving a long ball from goalkeeper Hidde Jurjus, securing a late 2–2 draw.[6]
In June 2023, Brittijn's contract was renegotiated and extended until 2025.[7] At that point, he had grown into a key player in midfield for De Graafschap.[8][9]