A 67-year-old man was referred to our department, after a vehicle accident, with multiple bone fractures and a left blunt diaphragmatic rupture. An emergency laparatomy was performed, and the left diaphragmatic defect directly sutured. Postoperatively, a delayed right diaphragmatic rupture occurred due to progressive inflammation and muscle devitalisation. The diagnosis was challenging because the right rupture became clinically evident later after extubation. Diaphragmatic reconstruction was performed through a right thoracotomy. A high index of suspicion should always be observed for missed or delayed bilateral diaphragmatic ruptures.