Adhesive wear extension in metal fretting contacts was previously related to the partial pressure of oxygen gas in a porous third body layer. Below a threshold value, the surface oxidation is no more possible and adhesive wear prevails in the inner part of the interface. The contact oxygenation concept (COC) allowing the prediction of the dioxygen partial pressure profile was recently simulated for a 2D surface analysis (i.e. 3D contact) using a numerical Advection-Dispersion-Reaction (ADR) approach. In this study, a simple explicit formulation is derived to capture COC response using a 1D surface analysis (i.e. 2D contact hypothesis).