A piston assembly and connecting rod therefor is provided. The connecting rod has an elongate body extending to an end for operable attachment to a piston. The end has a wrist pin bore extending between opposite sides of the body. The wrist pin bore has a wavy profile extending between the sides. The wavy profile has at least one concave surface with a valley extending along a circumferential direction of the wrist pin bore and convex surfaces having peaks extending along a circumferential direction of the wrist pin bore on laterally opposite sides of the valley. The peaks and valleys cooperate to form a smooth load gradient and uniform lubrication flow across the interface region between the wrist pin bore and the wrist pin extending therethrough.