is the force on particle i in the FG system and ⟨• • • ⟩ R N ,Ω N denotes an average over FG configurations that are mapped to CG configuration (R N , Ω N ). Equation ( ) generalizes the force-matching condition of the MS-CG method for isotropic CG particles to anisotropic particles. It shows that consistency between the FG and CG models in configuration space requires the force on a CG particle in a particular CG system configuration to equal the average total force acting on its constituent FG particles in FG configurations mapped onto the CG configuration. A full derivation of the expression for CG forces can be found in the SM, section SI.