A container holder system for attachment to a lawnmower handle assembly. In operation, the container holder system receives a beverage container and pivots with respect to the ground to prevent spilling from the beverage container. Optionally, the container holder system rotates with respect to itself to provide ease of use. The container holder system includes a cage assembly and a mounting device for securing the cage assembly to the lawnmower handle assembly. The cage assembly includes cage arms and a flange interface defined by the cage arms. The mounting device includes a gripping sleeve positioned between the cage arms and the lawnmower handle assembly and includes a clamp for drawing the cage arms and the gripping sleeve against the lawnmower handle assembly.