A cart assembly that is designed to hold and transport one or more ball hoppers. The ball hoppers have baskets that are supported by legs. The baskets are configured to hold some type of ball, such as a tennis ball or a golf ball. The cart assembly can transport the ball hoppers as they are standing on legs. The cart assembly has a platform that is supported by wheels. The wheels provide the platform with the ability to roll. Receptacles are present on the platform. The receptacles are sized, shaped and positioned to receive the legs of a ball hopper when the ball hopper is placed on the platform. Once a ball hopper is attached to the platform, the ball hopper becomes part of the cart assembly and can roll with the cart assembly from point to point.