Prior research has revealed that L1-Mandarin learners employed position-dependent repair strategies for European Portuguese /l/ and /ɾ/. In this study we examined whether this L2 prosodic effect can be attributed to a cross-linguistic influence and whether the replacement of the Portuguese rhotic by the Mandarin [ɹ] is due to perception or orthography. We performed a delayed imitation task with naïve Mandarin listeners and manipulated the presented input types (auditory form alone or a combination of auditory and written forms). Results showed that naïve responses were reminiscent of L1-Mandarin learners’ behaviour, and that [ɹ] was used almost exclusively in the presence of written input, suggesting that the prosodic effect attested in L2 acquisition of European Portuguese /l/ and /ɾ/ stems from cross-linguistic interaction between phonological categorization and orthography.