Achilles tendon injuries are rarely associated with osseous lesions. The combination of mediomalleolar fracture with Achilles tendon rupture has been reported as a rare combination injury in alpine skiers, but never before in basketball. This report presents an Achilles tendon rupture in a senior basketball player in combination with a non-displaced fracture of the medial malleolus. The osseous lesion was initially missed, because the tendon injury with all typical clinical and sonographical signs predominated. The routine X-ray examination was only done in the lateral and axial plane, because the examiner did not even think of an ankle fracture, since the description of the sports accident and the clinical signs were so typical for a sole tendon injury. This case report should remind us not to exclude an osseous or ligamentous ankle injury in those cases of acute Achilles tendon rupture especially if postoperative swelling and pain persist for a prolonged period.