  Scattering amplitudes for the massless QCD process, $q\bar{q}\to
q^\prime\bar{q}^\prime$, are calculated in the one-loop order in the
Feynman-Diagram (FD) gauge, where gluons are quantized on the light cone with
opposite direction of the three-momenta. We find non-decoupling of the
Faddeev-Popov ghosts and non-conventional UV singularities in dimensional
regularization. The known QCD amplitudes with asymptotic freedom are reproduced
only after summing propagator and vertex corrections. By quantizing gluons in
the Feynman gauge on the FD gauge background, we obtain the one-loop improved
FD gauge amplitudes.
