A resin-extended modified diene elastomer is based on a plasticizing resin and a diene elastomer having a number-average molar mass before modification Mn1 and a number-average molar mass Mn2 after modification, Mn1 and Mn2 being measured by triple detection size exclusion chromatography, the modified diene elastomer comprising branched chains corresponding to the following general formula (I)




the modified diene elastomer having an Mn2 of greater than or equal to 200 000 g/mol and has an Mn2/Mn1 ratio of strictly greater than 1.00.