Better solution than using negative vspace

fi-thesis-report.cls

@@ -72,10 +72,10 @@ práce}
 {\def\arraystretch{1.3}\tabcolsep=10pt
 \begin{tabularx}{\textwidth}{@{} l >{\it} l @{}}
 Název práce: & \begin{tabular}[t]{@{}l@{}}\@thesisName\end{tabular} \\
-Autor práce: & \@student \\
-\ifthenelse{\isundefined{\@supervisor}}{}{Vedoucí práce: & \@supervisor \\}%
-\ifthenelse{\isundefined{\@consultant}}{}{Konzultant: & \@consultant \\}%
-\ifthenelse{\isundefined{\@reader}}{\vspace{-1.3em}}{Oponent: & \@reader \\}%
+Autor práce: & \@student
+\ifthenelse{\isundefined{\@supervisor}}{}{\\Vedoucí práce: & \@supervisor}%
+\ifthenelse{\isundefined{\@consultant}}{}{\\Konzultant: & \@consultant}%
+\ifthenelse{\isundefined{\@reader}}{}{\\Oponent: & \@reader}%
 \end{tabularx}
 }
 \vspace{-0.5em}