Two-time world champion Williams overcame Anthony McGill 5-3 in Beijing to set-up the clash with Robertson. Williams has fallen out of the top 16, and will need to qualify for the world championships later this month, but was victorious when he last played Robertson at the Welsh Open earlier this year.
Mark Selby overcame a late-night workout before eventually beating world number 98 Stuart Carrington 5-3. It was a case of last-man standing for the world number two, who was a runner-up in Beijing last year, after Carrington ensured they remained at the table long after the matches around them had finished.
Shaun Murphy beat Jamie Cope 5-1 as he aims to win back-to-back world rankings titles, after tasting success at the Haikou World Open.
Local hopeful Ding Junhui easily won through to the last 32 as he cast aside John Astley 5-1, while fellow top-10 players Judd Trump, Marco Fu and John Higgins also progressed.