Meat consumption by early hominins is a hotly debated issue. A key question concerns their access to large mammal carcasses, including megafauna. Currently, the evidence of anthropic cut marks on proboscidean bones older than -or close to- 1.0 Ma are restricted to the archaeological sites of Dmanisi (Georgia), Olduvai (Tanzania), Gona (Ethiopia), Olorgesailie (Kenya) and La Boella (Spain). During an inspection of the almost complete carcass of Mammuthus meridionalis (FN3-5-MPS) from the Oldowan site of Fuente Nueva 3 (Orce, Spain, c. 1.2 Ma), a few traces compatible with human-made cut marks and carnivore tooth marks were found. From this finding and previous interpretations the following questions arise: When and under what conditions was FN3-5-MPS deposited? What is the nature of the marks found on the surface of the bones of this mammoth? To answer, we have conducted a high-resolution analysis of these remains, combining both taphonomic and microstratigraphic data. Our results, using microstratigraphic and micromorphological analyses of sediments based on thin-sections, show that this individual was deposited in a marshy environment. Subsequently, the carcass was exploited by hominins and large felids that left their marks on the surface of some of its bones. For this purpose, the identification and characterisation of both cut marks and tooth marks were performed using high-resolution 3D modelling, geometric morphometrics, and artificially intelligent algorithms. Based on the anatomical position of both the cut and tooth marks, we propose that both the hominins and the saber-toothed cats had early access to the animal. Finally, this paper shows how an interdisciplinary approach can shed detailed light on the particular story regarding the death and processing of the carcass of a female mammoth, deposited at Fuente Nueva 3.