I investigate a Breton paradigm where excorporation takes place from morphological amalgams such as inflected lexical verbs. I propose that Breton analytic structures with auxiliation in 'do' illustrate a case of excorporation outside of syntax, in realizational morphology. The distribution of Breton excorporation is directly dependent on the output of the syntactic module : word order. The trigger for excorporation, Late Expletive Insertion Trigger, is itself at the interface, after syntax and before phonology. Excorporation out of the inflected head asks for repair strategies in order to pass the Stray Affix Filter : 'do' support insertion leads to regular analytic structures in 'do' (to.know do.1SG, 'I know'). Another last resort strategy is to pronounce the lower copy of the lexical verb, which leads to doubling structures (to.know know.1SG, 'I know'). Idiosyncrasy of the latter confirms that repairs of excorporation are not syntactic.