Abstract: A rear binding (6) releasably clamps a heel (5) of a boot (1) to a ski (2). A front binding (4) which engages a toe (3) of the boot releases under lateral force towards the left or right side of the ski. A support assembly (8) engages a sole (7) of the ski boot to reduce frictional forces between the ski boot and ski which might impair the release of the front binding. The support device includes a stationary support (9) which is mounted to the ski and which defines a lateral groove (13) having a generally inverted T-shaped cross section. A movable element (10) which is slidably received in the groove has an upper surface that supports the boot sole. A friction reducing element (20), such as a layer of low coefficient of friction plastic is disposed between the movable element and the stationary support such that the movable element and the toe of the boot can move laterally with minimum frictional resistance.