Teacher behaviour and student motivation are well-known antecedents of student learning performance. However, their interaction effects remain under-explored, especially given the different types of teacher behaviour and motivation. This study2 involving students in a private Pakistani secondary school (n=367) examined these interaction effects on students' perceived learning performance. Our findings show that when students viewed their teachers as providing better teaching and classroom structure (termed structure), their extrinsic motivation influenced perceived learning performance more than intrinsic motivation did. Conversely, how students perceived that their teachers related individually and personally to them (termed relatedness) were more pertinent in enhancing intrinsic, than extrinsic, motivation. We also demonstrated that extrinsic motivation mediated the effects of structure on only perceived grade performance, whereas intrinsic motivation mediated the effects of relatedness on grade performance as well as confidence in ability and staying motivated. Further, perceived teacher behaviour was reciprocally influenced by intrinsic motivation, but not by extrinsic motivation. The study extends academic research into the nexus of teacher behaviour and motivation, especially the differential importance of intrinsic over extrinsic motivation. It also provides practical guidance to educationists on improving student performance through appropriate teacher training.