pathprob

\documentclass[
a4paper
]{scrartcl}

\usepackage{lmodern}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage{tikz}
\usetikzlibrary{intersections}

\listfiles

\begin{document}
\begin{center}
\begin{tikzpicture}[font=\sffamily\small]
\path[name path=aaa] (0,0) rectangle (10,0) node[midway, above] {aaa};
\begin{scope}[yshift=-2cm, below=of aaa, anchor=north]
\node[fill=red!20] at (2,0) {Test};
\end{scope}
\draw[fill=red] (aaa) -- (5,2);
\end{tikzpicture}
\end{center}
\end{document}