  We calculate the parametrically dominant next-to-next-to-leading order
corrections to four-fermion production e^- e^+ -> mu^- nubar_mu u dbar + X at
centre-of-mass energies near the W-pair production threshold employing the
method of unstable-particle effective theory. In total the correction is small,
leading to a shift of 3 MeV in the W-mass measurement. We also discuss the
implementation of realistic cuts and provide a result for the interference of
single-Coulomb and soft radiative corrections that can easily be extended to
include an arbitrary number of Coulomb photons.
