Rectangle Color and ImageFill

Ive come across an annoying issue when trying to set a color of a rectangle in combination with an ImageFill:

<Rectangle CornerRadius="5" Color="Red">
<ImageFill Url="{Image}" StretchMode="UniformToFill" MemoryPolicy="UnloadUnused" />
</Rectangle>

Works as expected, e.g. the rectangle is red and covered by the image when the image is loaded. However, when trying to pick up the color through each:

<Rectangle CornerRadius="5" Color="{Color}">
<ImageFill Url="{Image}" StretchMode="UniformToFill" MemoryPolicy="UnloadUnused" />
</Rectangle>

The Color of the Rectangle covers the Image, e.g. the Image doesn’t show…