Building on the endogenous routine dynamic perspective, we aim to understand the micro-foundations of capability transfer in post-acquisition integration. Based on a single, longitudinal case study of an acquisition in the consultancy sector, we apply a practice-based lens to study the intended combination of two existing routines in an acquisition process and why its implementation turned out to be a failure. Our findings suggest that seemingly matching capabilities were not compatible in practice as the underlying sequences of action were incompatible and their embeddedness in its intra- and inter-organizational ecology of routines was not considered. Our article sheds light on the role of routines in acquisition integration and contributes to literature by discussing a) the prevailing role of the interconnectedness of routines in effective capability transfer and b) discrepancies between ostensive and performative aspects of routines as impediments to the implementation of the pre-acquisition plan in the post-acquisition phase.