A gradient-index (GRIN) optical connector is disclosed that includes a GRIN lens having a central optical axis and front and back opposite endfaces. A plurality of optical fibers are optically coupled to the back endface of the GRIN lens and defines a first optical fiber bundle having an asymmetric arrangement relative to the central optical axis of the GRIN lens. The GRIN lens has a refractive index profile generally defined by an alpha profile having an alpha parameter α in a range 1.92≦α≦1.98. An optical fiber connector assembly formed by interfacing two of the GRIN optical connectors is also disclosed.