In an interconnected world, interdiscourse communication is essential for inclusivity and understanding in education. This study examines the language adjustment strategies used by Indonesian EFL pre-service teachers during their teaching practicum with Malaysian ESL learners at Maahad Tahfiz Darul Falah, Selangor. This study aims to explore the language adjustment strategies employed by Indonesian EFL pre-service teachers, the reasons for utilizing these strategies, and the view of Indonesian EFL teachers on the effectiveness of these strategies. This research employed a qualitative approach, specifically a case study, and gathered data through classroom observations and semi-structured interviews with five pre-service teachers. Triangulation of observational data and interviews, along with member checking, enhanced the validity of the data. The findings indicated that among the five pre-service teachers studied, three used convergence strategies, two used maintenance strategies, and none used divergence strategies. The reasons for employing these strategies varied, with convergence motivated by a desire to enhance understanding and emotional connections while maintenance was driven by comfort and confidence in teaching style. Convergence was seen as effective in enhancing students’ comprehension and engagement, while maintenance had less effect on these aspects. Future research could enhance the understanding of language adjustment strategies in multicultural classrooms by including more diverse participants over longer durations and employing various methods, such as reflection, narrative inquiry, and documentation. Subsequent researchers could also explore the effectiveness and influence of these strategies while examining their relationship with other aspects, such as technology in education.