Most theories of human language production assume that generating a sentence involves several stages, including an initial stage where the prelinguistic message is determined and a subsequent stage of grammatical encoding. However, it is contentious whether grammatical encoding involves separate stages of grammatical-function assignment and linearization. To address this question, we examined the mapping between the message level and grammatical encoding in two structural priming experiments in which German speakers choose between three different structures expressing ditransitive events. Although speakers showed a tendency to repeat the order of constituents (noun phrase-prepositional phrase, NP-PP, vs. NP-NP), they were additionally primed to repeat the order of thematic roles when constituent structure was constant (NPRECIPIENT-NPTHEME vs. NPTHEME-NPRECIPIENT). Experiment 2 found that the latter effect could not be due to persistence of the order of phrases referring to animate and inanimate entities. These results suggest a direct mapping of thematic roles to word order, consistent with a model in which the message is mapped onto syntactic structure in a single stage.