We study the structure of the Llevant ranges in Mallorca with special emphasis in the Cenozoic extensional evolution of the island, which we integrate in a new geodynamic model for the Westernmost Mediterranean. Mallorca underwent two rifting phases in the Oligocene and Serravallian, before and after the development of its Foreland Thrust Belt (FTB). The first extensional phase produced Oligocene semigrabens (29-23 Ma) that were inverted during the Early-Middle Miocene (23-14 Ma) WNW-directed FTB development. The second rifting phase produced the extensional collapse of the Mallorca FTB during the Serravallian (14-11 Ma). This later rifting was polyphasic, with NE-SW and NW-SE directed transport, resulting in an overall sequential, radial extension. The Oligocene extension affected great part of the Western Mediterranean, opening the Liguro-Provenzal and proto-Algerian basins after the collapse of the Palaeogene AlKaPeCa orogen, and Mallorca, its former hinterland. Continued plate convergence nucleated a new subduction system in the Early Miocene that initiated along the Ibiza transform, producing the Mallorca WNW-directed FTB and the subduction of the South-East Iberian passive margin. A process that individualized the Betic-Rif slab and initiated its westwards retreat. Serravallian extension occurred at the northern edge of the subduction system coeval to the Algero-Balearic basin opening. Extension initiated towards the SW direction of slab tearing and later rotated to a NW-SE direction, probably related to flexural and isostatic rebound. These processes drove the Alboran domain archipelago southwestwards until the Late Miocene, contributing to the present isolation of the Mallorca FTB from its Betic hinterland.