In the ever-expanding digital realm, a systematized and coherent legal framework regulating data-driven competition has emerged as a paramount concern in the European Union. At the heart of this intricate puzzle lie the General Data Protection Regulation (GDPR) and the Digital Markets Act (DMA) governing data protection and market contestability respectively. While the ‘without prejudice’ clause enshrined in the DMA seeks to harmonize their coexistence, the true extent of their compatibility and complementarity remains elusive. The juxtaposition of these two legislative pillars unveils nuanced conflicts and potential vulnerabilities at their intersection. If disregarded, these glaring blind spots might become an Achilles heel of the DMA and risk to weaken the DMA’s data-related ambitions.