Guided by self-determination theory, the study examined experiment-based models that linked teacher emotional support (TES) with students’ basic psychological needs (BPNs) satisfaction and frustration, the emotions of anxiety and enjoyment, and both emotional disengagement and engagement measured at three time points. An experimental group of 63 learners took part in a 10-week quasi-experimental intervention designed to enhance the three TES dimensions—positive climate, teacher sensitivity, and regard for students’ perspectives—while data from questionnaires and classroom observations were analyzed using ANOVA, ANCOVA, and PLS-SEM.
Results showed marked, upward shifts in students’ BPN satisfaction, emotions, and emotional engagement, culminating near the experiment’s conclusion. The PLS-SEM models demonstrated solid fit, accounting for 91 % and 94 % of the variance in emotional engagement at Time 2 and Time 3, respectively. Although TES itself did not exert a significant direct impact on engagement at any phase, its influence operated chiefly through learners’ BPN satisfaction and enjoyment. Overall, the findings supply empirical support for the benefits of a TES-oriented approach for L2 learners.