Online learning has grown considerably in recent years. However attrition rates from online courses indicate that not all learners are successful in such settings, and various factors have been identified as crucial to learner persistence. Research evidence suggests that motivation is one such factor. This study builds on previous studies by using self-determination theory (SDT) as an analytical framework to explore, in-depth, the motivation of pre-service teachers situated within an online learning context. In particular, the underlying concepts of autonomy, competence and relatedness from SDT were adopted as critical lenses to identify social and contextual influences which undermined the psychological needs of these learners. Most prominent among these in the current study were: high workload, assessment pressure, perceptions that the learning activity lacked relevance (autonomy-undermining), unclear and complicated guidelines, insufficient guidance and feedback from the instructor (competence-undermining), and communication issues with peers (relatedness-undermining). By not exclusively focusing on learners' autonomy needs as others have done, the paper offers a more extensive picture of undermining influences on motivation than has been previously identified in online studies.