Oskar Siira Sivertsen

Oskar Siira Sivertsen came through the Kristiansund BK academy after starting out at Dahle, joining the club's youth setup at around 12 or 13 years old. He made his senior debut for Kristiansund on 22 August 2020 against Sarpsborg 08, and in 2022 he was sent out on loan to Hødd, where he scored twice in five league appearances to gain first-team minutes. Back at Kristiansund, he eventually reached 72 appearances and 11 goals across all competitions for the club.

Sivertsen was named Norwegian First Division Young Player of the Month in October 2023, then repeated the feat a division higher, picking up the Eliteserien Young Player of the Month award in April 2024. On 4 February 2025 he signed for Go Ahead Eagles on a contract running until June 2028, with reports of the fee ranging between €150,000 and €1.1 million.

At his new club, Sivertsen was part of the squad that won the KNVB Cup in the 2024–25 season, though he watched the final from the bench. He has represented Norway extensively at youth level, moving through the age groups from Under-15 to Under-21, most recently collecting caps for the Under-21 side as of June 2025.