After the Olympics, Zersenay returned to Eritrea and trained for one month to prepare for the 2008 World Half Marathon Championships in Rio de Janeiro. He won his third consecutive title over the half marathon distance with ease, taking the lead early on and beating the second-placed Patrick Makau Musyoki by almost two minutes. His success caused much celebration in his home country, so much so that the President of Eritrea greeted him at the airport upon his return. With a strong history in the half marathon, Zersenay announced he would try the full marathon distance the following season.