World number 47 Robertson was on the wrong end of a 6-0 scoreline against 18th-ranked Mark Williams in a UK Championship second round tie which lasted just 97 minutes.
Robertson has been in pretty decent form of late and was a 6-1 winner over Zhou Yuelong in round one, but scored 10 points or fewer in four of the six frames against Welsh cueman Williams.
Williams edged a tight opening frame 68-52, but Robertson didn’t pot a ball in frame two, which Williams clinched thanks largely to a break of 51. The 39-year-old won the third on the brown and eased through the fourth, finishing the frame with a run of 55.
Robertson didn’t score a point in frame five as Williams knocked in a break of 83 and Williams sealed victory in the next to book his place in the last 32.
Mark Davis, the world number 19 from St Leonards, will contest his second round match against Liam Highfield from 7pm tonight. Davis - a semi-finalist in the event two years ago - was a 6-2 victor against Jak Jones in round one.