Annie Au Wing-chi's campaign at the World Open in Manchester got off to a flying start when she defeated world number 17 Samantha Teran of Mexico in one of the day's biggest upsets. The Hong Kong number two wrapped up the match in 36 minutes with a 11-5, 11-4, 3-11, 11-5 victory. Hong Kong champion Rebecca Chiu Wing-yin joined Au in the second round after she came back from two games down to defeat England's Lauren Briggs 8-11, 6-11, 11-5, 11-6, 11-6. Hong Kong coach Tony Choi Yuk-kwan was delighted with the pair's fine start. 'It's a good day for Hong Kong squash, having two women in the last 16 at the World Open for the first time,' Choi said. Choi praised Au on her upset victory. 'Annie is playing well and is in good form. She didn't have anything to lose and there was no pressure on her to win,' he said. However, Choi warned: 'Rebecca plays Nicol David [world number one] again, while Annie takes on Natalie Grinham [world number two], so they'll just have to go out and do their best.' David (pictured) started her bid to regain the World Open title with a 11-6, 11-3, 11-2 win over compatriot Sharon Wee.