This study aims to show how writers contextualize their findings in order to demonstrate the legitimacy of new research within an academic discipline. While huge efforts have been devoted to the identification of the Moves and Steps in Research Article (RA) Discussion sections, how writers justify the value of new research through evaluative comparisons with prior studies, in order to transform empirical results into knowledge claims, has been less studied. The present study conducted a rhetorical analysis of this critical act, evaluative comparison, drawing on a genre-based description of Moves and Steps. Based on an analysis of 12 applied linguistics research articles, this study reveals that six rhetorical Steps are typically deployed to legitimize new research through evaluative comparison, and illustrates their possible variations in schematic patterns. The findings not only contribute to our understanding of the knowledge construction process through argumentation, but also have important pedagogical implications for the writing practices of novice English researchers.