World number 19 Wong Chun Ting of Hong Kong suffered a shock 4-2 defeat to Denmark’s Zhai Yujia in the second round.

After his surprise win Yujia, ranked 179 in the world, now faces world number 71, Poland’s Jakub Dyjas in round three.

Another shock came when the world's number 22 Belarussian Vladimir Samsonov was knocked out by China's Xu Chenhao, ranked 210 while Japanese 18-year-old Shunsuke Togami knocked out world number 32 Croatia’s Tomislav Pucar.

Portugal’s Yu Fu was the highest-ranked player to be knocked out of the first preliminary round of the women’s singles as the number 41 lost 4-2 to number 175 Amy Wang of the United States.

Another notable exit came from Ukraine’s Ganna Gaponova, world number 67 who was also defeated 4-2 to world number 126 Lisa Lung from Belgium.

Singles action returns on January 29, with the winners in the final preliminary round making the last 32 bracket against the 16 seeded players.