[5] He made his professional debut on 1 June 2020 in a 1–0 away loss to AGF, coming on as a substitute in the 47th minute for Mart Lieder.
[6] His first goal for the club came in the play-offs for European football, scoring in a 2–1 away loss to Randers FC on 11 July after making a start.
[7] In the return game, he secured advancement for OB by scoring a brace as the team won 2–0 at home.
[8] Fenger finished his first season in the first team with 10 appearances, in which he scored four goals – all in the play-offs for European football, which OB eventually lost out after a 1–0 loss to AGF.
[9] Fenger struggled to find playing time the following season, as he was sidelined with a knee injury which he suffered in a loss to Brøndby IF on 8 November 2020.