Quasi fission process is a non-compound nucleus process, a major challenge in the formation of super heavy evaporation residues and elements. It is well known that the entrance channel parameters such as mass asymmetry, deformation of the reaction partners, fissility etc, play important role in the dynamics of fusion-fission process. We report the onset of quasi fission process for very asymmetric reaction 24Mg+186W forming the composite system 210Rn. The charge product ZpZt is very much less than 1600 in the present study. Comparisons with systems where quasi fission is reported in literature indicates the role of deformation in the dynamics. Mass distribution of different beams on same target hints the possible role of projectile deformation in the case of highly deformed projectiles like 24Mg. Experimental results and observations will be discussed in detail.