Calderón-Zygmund estimates refer to either the theory of singular integral operators or its historically principal application to partial differential equations: bounding the gradient of a solution to an elliptic equation by the source data on the right hand side. The theory of singular integrals was revolutionazed by the emergence of so-called sparse estimates around 2015. In this talk, I discuss a recent joint work with Hua-Yang Wang and Yuanhong Wei, where we treat gradient estimates for divergence form elliptic equations in terms of sparse bounds.