There are numerous studies showing processing advantages for collocations, but none of them so far takes into account the fact that the morphological form of a collocation varies to fit the context. Questions whether collocations retain their processing advantage when their morphological form changes and how or if different morphological forms of the same collocation are related in the mental lexicon have remained unanswered. The present study starts addressing these questions. The article reports an eye-tracking experiment during which 37 native speakers of Lithuanian (a morphologically complex language) read 10 short stories with embedded verb + object collocations in three different morphological forms (infinitive + accusative, past tense third person + accusative, and passive attributive participle + nominative) as well as control phrases (60 target items per participant). Mixed-effects analysis showed that collocations in all three morphological forms were processed with comparable facilitation. The study also analyzed whether the phrasal form frequency of the specific morphological form or the base frequency of that collocation works better at predicting reading behavior. The results show no clear advantage of one or the other. Potential reasons for this finding are discussed.