  A new method to measure the top-quark mass in high energetic hadron
collisions is presented. We use theoretical predictions calculated at
next-to-leading order accuracy in quantum chromodynamics to study the
(normalized) differential distribution of the \ttbaronejet cross section with
respect to its invariant mass $\sqrt{\sttj}$. The sensitivity of the method to
the top-quark mass together with the impact of various theoretical and
experimental uncertainties has been investigated and quantified. The new method
allows for a complementary measurement of the top-quark mass parameter and has
a high potential to become competitive in precision with respect to established
approaches. Furthermore we emphasize that in the proposed method the mass
parameter is uniquely defined through one-loop renormalization.
