The mainland contingent lost their first match at the World Championships when Zheng Bo and Zhang Jiewen, a new mixed doubles pairing being groomed as a potential world number one partnership, went out in the first round, beaten 15-11, 15-12 by the South Korean 12th seeds Kim Young-hyun and Lee Hyo-jung. Although the match, which decided the second-round opponents for Hong Kong's Albertus Susanto Njoto and Wang Cheng, went according to the rankings, Chinese head coach Li Yongbo had hopes that Zheng, 20, and Zhang, 22, would be the surprise package of the tournament. 'They lost because of their tactics were wrong,' Li said. 'They played too slowly. We asked them to play at a high pace, but Zheng Bo especially played too slowly. We needed him to make the transition from defence to attack more quickly. Without speed his smash is ineffective.' However, Li said the defeat was a timely warning to the squad. 'It's good, because it's a reminder to the other players that the real fight is just starting.' Not that Chen Lin and Jiang Xuelian needed reminding after being taken to three sets in an 80-minute tussle with Malaysia's Chin Eei-hui and Wong Pei-tty in the women's doubles before winning 15-2, 13-15, 15-13. In stark contrast, fourth seed Gong Ruina spent just eight minutes on court as she massacred Crisa Georgali of Greece without conceding a single point.