  We show that the O(Lambda) ambiguity in the pole mass can be fixed in a
natural way by introducing a modified nonperturbative V-scheme momentum space
coupling tilde-alphaV(q) where the confining contributions have been subtracted
out. The method used is in the spirit of the infrared finite coupling approach
to power corrections, and gives a non perturbative definition of the `potential
subtracted' mass. The short distance expansion of the static potential is
derived, taking into account an hypothetical short distance linear term. The
magnitude of the standard OPE contributions are estimated in quenched QCD,
based on results of Luscher and Weisz. It is observed that the expansion is not
yet reliable at the shortest distances presently measured on the lattice.
