This small muscle in the back of the knee can be overlooked as a calf muscle strain. Its actual job is to bend the knee from a fully straight and locked position and allow the hamstrings to take over. It can be strained with movements that rapidly lock the knee out and trauma. It can also be strained with sprinting and in particular hurdling.
Once the diagnosis is made then the rehab can be tailored accordingly. If you are struggling with a niggle in the back of the knee then get it assessed as this muscle can linger on.