Autologous osteochondral transplantation (AOT) is an effective treatment for large Osteochondral Lesions of the Talus (OLT), however little is reported on an athletic population, who are likely to place higher demands on the reconstruction. The aim is to report the outcomes of large OLT (>150mm2) within an athletic population. The study population was limited to professional or amateur athletes (Tegner score >6) with an OLT of size 150mm2 or greater. The surgical intervention was AOT with a donor site from the lateral femoral condyle. Clinical outcomes at a minimum of 24 months included Return to Sport, VAS and FAOS Scores. In addition, graft incorporation was evaluated by MRI using MOCART scores at 12 months post-surgery. 38 athletes including 11 professional athletes were assessed. Mean follow-up was 46 months. Mean lesion size was 249mm2. 33 patients returned to sport at their previous level and one did not return to sport (mean return to play 8.2 months). Visual analogue scores improved from 4.53 pre-operatively to 0.63 post-operatively (p=0.002). FAOS Scores improved significantly in all domains (p< 0.001). Two patients developed knee donor site pain, and both had three osteochondral plugs harvested. Univariant analysis demonstrated no association between pre-operative patient or lesion characteristics and ability to return to sport. However, there was a strong correlation between MOCART scores and ability to return to sport (AUC=0.89). Our study suggests that AOT is a viable option in the management of large osteochondral talar defects in an athletic population, with favourable return to sport levels, patient satisfaction, and FAOS/VAS scores. The ability to return to sport is predicated upon good graft incorporation and further research is required to optimise this technique. Our data also suggests that patients should be aware of the increased risk of developing knee donor site pain when three osteochondral plugs are harvested.