  Homogeneous power counting in Non-Relativistic QCD (NRQCD) implies the
simultaneous existence of both soft and ultrasoft gluons. In the velocity
renormalization group (vNRQCD) formalism we show that operators involving soft
fields interacting with heavy potential quarks can be put in a manifestly gauge
invariant form by utilizing gluon and quark building blocks which contain
Wilson lines, and are analogous to those used in the soft collinear effective
theory. This leads to several simplifications, in particular significantly
reducing the size of the operator basis, which stream-lines matching and
anomalous dimension calculations at subleading order in the velocity expansion.
Also, soft ghosts no longer couple via potential like interactions to the heavy
quark fields, and hence do not appear until two loops. Furthermore the the
color structures that appear at each order in $\alpha_s$ in the static
potential are only those which should arise according to non-Abelian
exponentiation. We also discuss how zero-bin subtractions clarify the role of
$i\varepsilon$ terms in the heavy quark propagator poles carrying soft momenta.
Even though the choice of the direction of the soft Wilson lines in our
building blocks does not matter, there is still a limited set of consistent
choices, and the predicted form of the eikonal poles does influence results at
two-loops and beyond.
