Trying to append a file to a tarball through a pipe

I am trying to execute a simple pipeline which should gunzip a file and send the result to stdout. This is ten piped into a tar command which to my knowledge should append the file I specify. I use a hyphen to denote the stdin decompressed tarball which I am trying to append to. gunzip -c sandbox.tgz | tar rvf - hongkong.mp4 I receive the following response when I execute the command tar: Options '-Aru' are incompatible with '-f -'