We investigated how the lexical and sublexical processes interact in spelling using an articulatory suppression task to disrupt the sublexical process in a dysgraphic patient (JDO). Using a similar task, Folk et al. (2002) found evidence that the sublexical process interacts with the lexical process by strengthening a target word's graphemes. We replicated the findings of Folk et al. in a patient with a more severe deficit to the lexical process. We compared the error patterns produced under normal spelling conditions versus spelling during articulatory suppression and found an increase in lexical substitution errors ("thaw"-->T-H-O-U-G-H) under articulatory suppression. These findings indicate that by strengthening a target word's graphemes, the sublexical process helps to create an advantage for a target word over form-related word neighbours that compete with it for output.