Understanding and controlling the self-organization of functionalized sites are crucial in biological systems, in catalysis, and to target drug delivery. Here we investigate the possibility of spatiotemporal self-organization offered by the development of sequence-controlled polymers. As a key factor in reducing the configurational entropy of a chain, confinement can enhance or hinder the ordering of chain segments. Using molecular dynamics simulations and scaling concepts, we show that the segments of a closely grafted chains inside a patch are radially localized under planar confinement. We investigate the statistical properties of this self-organization and show that it results from an interplay between confinement and excluded volume between monomers. Increasing the length of polymers as well as the number of chains inside the patch enhances the localization and spatial sequencing order of the segments.