A beverage-retaining insert is used to retain and orient a smaller beverage container, including but not limited to a soda can or beer bottle, within a larger beverage container, including but not limited to a tumbler, thermos, or travel mug. The larger beverage container is herein referred to as the tumbler. The apparatus is also configured to prevent damage and unwanted shifting or movement of the bottle or can relative to the tumbler. The apparatus includes a retaining lip, a tubular brace, a tubular cushion, and a sealing mechanism. The retaining lip positions the apparatus atop a tumbler. The tubular brace enables arrangement of the apparatus within a tumbler. The tubular cushion provides support for a beverage container. The sealing mechanism retains the position of the present invention against the inside of a tumbler. Thus, the apparatus efficiently and effectively retrofits a tumbler to enable support of a beverage container.