The 2007 season saw Sato achieve a career peak. He was the runner-up behind Atsushi Fujita at the Beppu-Ōita Marathon. He was one second off his best at the Sapporo Half Marathon, taking third on the podium. At the 2007 IAAF World Road Running Championships he broke the Asian record for the half marathon with a time of 1:00:25 hours. This brought him ninth place overall, but he was one of only two non-African-born runners to finish in the top ten (alongside Marilson dos Santos). At the end of the year he was the first Japanese runner home at the Fukuoka Marathon and his run of 2:07:13 hours for third place made him the fourth fastest Japanese marathoner ever and gained him a spot on the Olympic team.