Vascular injuries represent a rare cause of shoulder pain and functional limitation among overhead athletes. Complaints of heaviness, fatigue, paresthesias, and effort-related pain should prompt the sports medicine clinician to consider vascular pathology as a possible cause of such symptoms. Position-dependent compression of the subclavian and axillary vessels within the thoracic outlet may result in functional limitation and a decline in overhead athletic performance, particularly when symptoms occur in the dominant upper limb. Treatment options include physical therapy and (in the case of thrombus) thrombolysis, but surgical decompression of the neurovascular bundle is generally advocated. This article reviews the diagnosis and management of effort thrombosis (also known as Paget-Schroetter syndrome), arterial thoracic outlet syndrome, and entrapment of the posterior circumflex humeral artery within the quadrilateral space. Familiarity with these conditions may help to minimize the risk of delayed diagnosis and associated morbidity.