Two "deviated" uses of the perfective / imperfective aspectual pair in Slavic languages, i.e. what has been traditionally called aspectual competition, will be examined here. The tool chosen for such analysis will be the invariant value established for these grammatical forms by Adamczewski's phases' theory or metaoperational grammar.
For this purpose the discursive contexts in which each form appears will be considered, as an essential to understanding and confirmation of the invariant value activating them, besides the different discursive effects of meaning they might generate in a given situation.