The influence of vector backgrounds with restored Lorentz invariance on
non-abelian gauge field theories is studied. Lorentz invariance is ensured by
taking the average over a Lorentz invariant ensemble of background vectors.
Like in the abelian case [hep-ph/0506210], the propagation of fermions is
suppressed over long distances. Contrary to the fermionic sector, pure gauge
configurations of the background suppress the long-distance propagation of the
bosons only partially, i.e. not beyond the leading contribution for a large
number of colours.Comment: 6 pages, no figure