The 2007 All-Africa Games represented a double landmark victory for Zersenay: he became the first Eritrean medallist in the competition's history, and won his first ever gold medal on the track, sealing victory in the 10,000 m final with a Games record time of 27:00.30. The following month he competed at the 2007 World Championships in Athletics, and he edged closer to a podium finish – he led the 10,000 m race up to the 8 km mark, setting a fast pace, but ultimately ended up in fourth position. Preparing for the road championships that year, he ran the 10-mile Dam tot Damloop race in September and won in 45:51 (the world's fastest that season), finishing some distance ahead of runners up Bernard Kipyego and James Rotich. Zersenay emphasised his position as one of the world's most dominant half marathon runners with a second victory at the 2007 IAAF World Road Running Championships in Udine, Italy. Although he was close to world record pace at the 15 km point, he slowed behind the leading pack of Makau Musyoki, Evans Kiprop Cheruiyot and Deriba Merga. In the final kilometre, he burst away to take the lead and the gold medal, setting a national and championship record time of 58:59 in the process. Following these achievements, a medical team did a study of his running economy and found him to be one of the most efficient runners ever to be tested.