Miller scored the opening goal in Rangers' 2017–18 season against Progrès Niederkorn in the Europa League on 29 June 2017. Despite his goal, Rangers went on to lose 2–1 on aggregate, giving Progrès their first ever European win. Miller was dropped from the Rangers first team in September 2017. This came after Pedro Caixinha had criticised some of the team's Scottish players in a meeting after a 2–0 defeat by Celtic. Caixinha then suggested that a Rangers player had leaked team information to opponents, which led journalists to surmise that Miller had been the source. Caixinha was sacked in late October, and Miller was reinstated to the Rangers team by caretaker manager Graeme Murty; in his first game back, Miller scored two goals in a 3–1 win against Hearts.