[3][4] On 14 February 2018, aged 15, Collander was promoted to Skiljebo's senior team, competing in Division 2, Sweden's fourth tier.
[9][10] On 5 July 2020, Collander made his debut for Örebro in Allsvenskan, in a 1–2 loss to IK Sirius, coming on as a late substitute.
[18][19] Collander featured in the final of the 2021–22 Svenska Cupen, in which Hammarby lost by 4–5 on penalties to Malmö FF after the game ended in a 0–0 draw.
[20][21] On 22 July 2022 after making five appearances in Allsvenskan, it was announced that Collander would be sidelined for several months due to an other knee injury,[22] eventually leading to him missing the rest of the 2022 season.
[26] His father Conny Collander is a former footballer who represented Västerås SK between 1989 and 1996, mainly in the Swedish second tier, before he was forced to retire due to several knee injuries.