The paper argues that integration of code-switched items into the Matrix Language is not a straightforward process and does not entirely depend on the structural characteristics of the languages involved. Estonian-Russian code-switching is instructive because both languages are rich in inflectional morphology. Full integration of Estonian nouns into the Russian matrix means gender assignment and adding of inflection (case, number, or case and number). Russian-Estonian code-switching data demonstrate a wide range of possibilities for integration. Zabrodskaja (2009) specifies six gradations of morphological integration, whereby morphological integration and phonological adaptation do not depend on each other: an Estonian item may show high phonological adaptation and no morphological integration into Russian, and vice versa. Empirical observations show that there are instances where Russian inflectional morphology is absent, although the Estonian noun fits structurally into Russian declension classes. The paper compares the integration of Estonian nouns into Russian morphosyntax in speech and in blogs. Both sets of data show similarities as far as types of integration are concerned. Morphological integration is often a matter of individual preference and variation rather than structural compatibility with the Russian matrix.