This is an attempt to build a visualization pattern showing combinations among items in a single list. It is inspired by a device I remember from printed maps, showing distances between cities - usually printed in an unused corner.
This pattern currently works best for combinations that are direction-agnostic. In this example, the datasete illustrates how often a group of soccer players appeared together over the course of a single season. For bi-directional combinations a different strategy may be needed, or perhaps a more nuanced design at each intersection.