Accepting the Komar mass definition of a source with energy-momentum tensor Tµν, and using the thermodynamic pressure definition, we find a relaxed energy-momentum conservation law. Thereinafter, we study some cosmological consequences of the obtained energy-momentum conservation law. It has been found out that the dark sectors of cosmos are unifiable into one cosmic fluid in our setup. While this cosmic fluid impels the universe to enter an accelerated expansion phase, it may even show a baryonic behavior by itself during the cosmos evolution. Indeed, in this manner, while Tµν behaves baryonically, some parts of it, namely Tµν(e) which is satisfying the ordinary energy-momentum conservation law, are responsible for the current accelerated expansion.