Ubuntu – Overwriting files when extracting from a tar archive

I play OpenTTD. There are three versions available and I want to have all three; stable, testing and nightly. I downloaded and compiled the source code for all three with no problems. The issue is when I want to compile a new version. When I extract the tar.xz file into /usr/lib/games/openttd-trunk/ the old files aren't overwritten. Instead, a new directory is created called openttd-trunk-r26175.

Is there any way to extract the files from the archive directly into /usr/lib/games/openttd-trunk/? That way I can just simply make without having to ./configure every time.

EDIT: I don't think I made clear that the archive has the source files inside a single folder called openttd-trunk-r26175. What I want to do is extract all files from that folder, but not the folder itself.