This study investigates the effect of loading frequency and hydrogenation to instigate the White Etching Areas (WEAs) formation under severe sliding condition of bearing steel. Experiments were carried out at 1.5 Hz and 4.5 Hz loading frequencies by varying the contact pressure from 1 to 2 GPa using dynamic load Pin-on-Disc (PoD) tribometer. Steel-on-steel tribo-pair was lubricated by two different lubricants, PAO and real-time hydrogenating oil, under boundary lubrication. Synergic interaction between hydrogen enhanced and mechanical stress induced drivers on WEAs formation was established. Subsequently, quantitative insights on the catalysing behaviour of the individual and concurrent actions of drivers were elucidated. Sequential evolution of butterfly around the non-metallic inclusion from the primitive stage was revealed in pure sliding through metallographic investigation. © 2019 Elsevier Ltd