A structurally supportive backer panel formed to fit within the recesses of a form liner to support the form liner when casting textured surfaces into concrete. The backer panel has a series of protrusions which fit within the recesses of the form liner in order to prevent the concrete pressure from deflecting and buckling the form liner. When the wet concrete is poured into a form fitted with the backer panel and form liner, the concrete fills the form and contacts the form liner, wherein the backer panel ensures that the shape of the form liner is not affected by the pressure and weight of the concrete.