Patterson made his European debut on 10 December 2020, starting in a 2–0 away win against Polish side Lech Poznań.[5] He scored his first goal for the club on 25 February 2021, in a UEFA Europa League match against Royal Antwerp, scoring 16.6 seconds after coming on as a second half substitute.[6] Patterson played regularly for Rangers during the later part of the 2020–21 season, deputising for the injured James Tavernier, until he was suspended for breaching coronavirus pandemic rules.[7]