The defending world champion David Oliver won the 110-meter hurdles at the Shanghai Diamond League meet, but it was the recently retired Chinese hurdler Liu Xiang who got the biggest ovation. Liu became one of China’s most celebrated athletes after winning the hurdles at the 2004 Athens Olympics. He retired a month ago at 31 because of recurring injuries. With Liu not in the race, Oliver, of the United States, edged Orlando Ortega of Cuba to win the gold in 13.17 seconds. Aries Merritt of the United States was third. After the race, a tearful Liu was honored on the track and then jogged around the stadium with Merritt and Oliver.