Introduction: Ruptured abdominal aortic aneurysm (AAA) is not uncommon to cause coagulopathy. Warfarin use in patients presented with ruptured AAA can further complicate the preparation for surgical intervention and affect prognosis. Case Report/Description: We report a case of a 57-year-old man on warfarin for mitral valve replacement (MVR), presented with contained rupture of mycotic infrarenal AAA. He received multiple transfusions of fresh frozen plasma (FFP), did not respond to three-factor prothrombin complex concentrate (3F-PCC) and required intravenous Vitamin K1 pre-surgery. The patient successfully underwent the open aneurysmectomy and inlay graft repair. Post-surgery, his INR raised spontaneously up to 2.54. On day-13 post-surgery, his INR fell below 2.0 and was re-initiated on anticoagulation. Discussion/Conclusion: Persistent and rebound coagulopathy is possible in ruptured AAA. Corrective treatment with FFP or 3F-PCC alone does not always guarantee the successful reversal of coagulopathy. Co-administration of vitamin K may be needed to prevent rebound coagulopathy. This case emphasised the importance of rigorous coagulation profile monitoring in patients on warfarin presenting with ruptured AAA.