Plasticising system which can be used for the plasticizing of a diene rubber composition, characterized in that it is based on an MES or TDAE oil and on C.sub.5 fraction/vinylaromatic copolymer resin, in particular a copolymer of a C.sub.5 fraction and of stirene resin. Rubber composition exhibiting an improved abrasion and cut resistance, said composition being based on at least a diene elastomer, a reinforcing filler, a crosslinking system and a plasticising system comprising between 5 and 35 phr of an MES or TDAE oil and between 5 and 35 phr of such a resin (phr=parts by weight per 100 parts of elastomer). Process for preparing such a composition, use of said composition for the manufacture of a finished article or of a semi-finished product intended for a motor vehicle ground-contact system, in particular a tire and a tread of such a tire.