In March 2004 Gebremariam showed that he had fully progressed from the junior ranks by winning two silver medals at the World Cross Country Championships, one over the short course and one over the long course; in essence, were it not for his countryman Kenenisa Bekele, he would be one of only two men ever to have claimed short and long course victories at the same Championships. He was selected for the Ethiopian Summer Olympic 5000 metres team along with Kenenisa Bekele and Dejene Berhanu, where he finished fourth, 0.25 seconds behind bronze medalist Eliud Kipchoge of Kenya.