In a 41-year-old man with an abnormal left lower lobe opacity on a chest radiograph, magnetic resonance (MR) angiography showed a large abnormal vessel extending from the left side of the descending thoracic aorta, supplying the left lower lobe. Furthermore, the lung parenchyma showed no evidence of sequestrated lung. This entity corresponded to type-I of intralobar pulmonary sequestration, as classified by Pryce.