The primary purpose of this study was to investigate an L2 learner's motivation during his involvement in language learning. Specifically, it was sought to conceptualize the (de)motives that might have an impact on the participant's language learning process and to reconceptualize, in this sense, the process above referring to the Activity Theory (AT). To this end, this study attempted to examine whether there were any changes in his motivation within the framework of AT. The scrutiny of data revealed that the changes stemming from the COVID-19 pandemic had a negative influence on Ahmet's language learning process. Although he was relatively motivated as he started as a language learner, the new changes he had to adapt to amidst the outbreak externally affected his learning experiences, leading to demotivation. The present paper argues how this change can be captured by referring to Engeström's (1999, 2009) triangle model. Further discussions and implications are provided in the study.