Teachers and teacher candidates have been documented using deficit discourse about multilingual learners (MLs), but little is known about how dialogic interactions take place or how such language is challenged in real time. This study examines how undergraduate teacher candidates (TCs) engage in a simulated conversation with a teacher colleague who uses deficit discourse toward MLs. The resulting data highlight how TCs use both resistance strategies to navigate deficit discourse, while also tacitly endorsing and approving deficit discourse at other conversation markers. Implications center on how schools of education can use simulations as practice-based spaces to challenge deficit discourse.