We describe an unpredictable clinical scenario involving an intraoperative vascular injury during an elective total shoulder arthroplasty. Shortly into the procedure, the patient became acutely hypotensive due to frank hemorrhage. The patient experienced a complete transection of the third segment of the axillary artery caused by an unrecognized bone fragment, suspected to have dislodged into the joint space following a traumatic ground-level fall 12 months prior. Emergency vascular surgical intervention was required for hemostasis.