It is shown that a non-relativistic power-law potential model for the heavy quarks in the form V(r)=Ar^v+V₀, (A, ν>0) acquires relativistic consistency in generating Dirac bound states of $$Q\bar Q$$-system in agreement with the Schrödinger spectroscopy if the interaction is modelled by equally mixed scalar and vector parts as suggested by the phenomenology of fine-hyperfine splittings of heavy quarkonium systems in a non-relativistic perturbative approach.

A heavy quark antiquark potential is suggested connecting asymptotic freedom and quark confinement in a unified way. Theα_g(q²) calculated using Borel summation technique with three loop agrees with the two loopβ-function up tog²/4π≅ 1.1 but changes appreciably afterg²/4π=1.5. The potential so derived satisfactorily explains the $$c\bar c$$and $$b\bar b$$spectrum.