The authors report the successful repair of a Crawford type III thoracoabdominal aortic aneurysm (TAAA) with a thrombosed infrarenal component using a modified hybrid technique without aortic clamping in a high-risk patient. A 64-year-old male with a history of hypertension, diabetes, and severe chronic obstructive pulmonary disease presented with acute on chronic backache and bilateral short distance claudication. A computerized tomography scan demonstrated a large, nonleaking Crawford type III TAAA with thrombosed infrarenal component of the aneurysm. In addition, both common iliac arteries were occluded with the chronic thrombus. A single-stage, modified hybrid procedure involving an aortobifemoral bypass without aortic clamping, debranching of right renal, superior mesenteric, and celiac arteries as well as an endovascular repair of the thoracic aneurysm was performed. Unfortunately, despite a technically sound repair, the patient died postoperatively from a massive pulmonary embolism. TAAA with a thrombosed infrarenal aorta and bilateral common iliac arteries can be repaired using a single-stage modified hybrid procedure without aortic clamping in high-risk patients who cannot tolerate thoracotomy and aortic cross clamping.