Popliteus tendon injuries most often occur in a traumatic setting with damage to multiple other knee structures. Isolated popliteal injuries, however, are rare. To our knowledge, there are no cases of a female pediatric patient with an intrasubstance popliteal tendon rupture in the current literature. This case report aims to illustrate symptoms, imaging, and treatment of an isolated popliteal tendon rupture in an adolescent female. An athletic 14-year-old female presented with right knee pain 4 weeks after a basketball injury in which she dove for the ball and fell, twisting and striking her knee. She had diffuse pain on both sides of the right knee for 3 weeks and pain with running, jumping or twisting. The knee exam was otherwise unremarkable. A right knee MRI demonstrated a complete rupture of the popliteal tendon. No other knee injuries were visualized. The patient was treated non-operatively and gradually returned to normal activities and sports at 6 weeks post injury. On 6-year follow up, the patient had no residual pain or instability and was able to play basketball without difficulty. Isolated popliteal tendon ruptures are extremely rare and difficult to diagnose given non-specific clinical exam findings. While these ruptures can be difficult to visualize on MRI, imaging can help to clarify the diagnosis by ruling out other injuries with similar clinical presentations. In the case of this young and active patient, diagnosis and full recovery without limitations were achieved with 6 weeks of conservative management.