A 59-year-old male presented with a primary synovial sarcoma around his knee. Two months after resection, he presented with a new, rapidly-growing mass in the ipsilateral proximal thigh. A biopsy of the new mass demonstrated a pleomorphic liposarcoma, distinct from the prior synovial sarcoma. He underwent neoadjuvant radiation, followed by wide resection. He is now undergoing surveillance for recurrence. While 2 distinct primary sarcomas developing in rapid succession is rare, this case emphasizes the need for a complete work-up, including obtaining a tissue diagnosis for suspected recurrent lesions as this may alter treatment and follow-up recommendations.