Methods and apparatuses for applying coatings on a moving web are provided. A coating die and a back-up roll engage with each other. The back-up roll includes a shell rotatably supported by a pressurized air layer. When a coating material is dispensed from the coating die onto the web to form a liquid coating, the pressure of the air layer is controlled such that the shell translates in space to balance forces from the air layer and the coating bead, while the web is being translated to drive the shell.