With the help of Jorge, Hrvoje, SIdo and MonkeyDragon we discover two key facts that will help to decode FIFA 11 .rx3 files. The first step was to discover that .rx3 files are compressed using zlib. After that Jorge found out that textures are decoded ard dds ones ( DXT5 ). So now we need to build a tool that allows to unzlib files and then recreates header of dds files. We will keep you informed about our progress.
First textures exported by hand