Selby fell to a 4-3 defeat in his round of 32 clash with Jack Lisowski, who rattled off a break of 96 in frame five to go with a 65 in the second.
Lisowski moves on to meet Tom Ford, who recovered from Martin Gould’s opening gambit ton to win 4-2.
Robertson meanwhile came from two frames down to see off Jamie Burnett 4-2, hitting the match’s highest break of 82 in frame four.
In the last 16, the Australian will play Barry Hawkins, who wasted little time whitewashing Li Hang with runs to 100 and 75 along the way.
There was another shut-out on day one as two-times Haikou World Open winner Mark Allen breezed past Mark Davis 4-0 to set up a date with Joe Swail.
Swail, who remains unsure if he’ll return to the professional tour this season, shocked Welsh Open champion Stephen Maguire by taking a last-frame decider to win 4-3.
PTC Grand Finals last 32 results
Martin Gould 2-4 Tom Ford
Neil Robertson 4-2 Jamie Burnett
Stephen Maguire 3-4 Joe Swail
Barry Hawkins 4-0 Li Hang
Mark Allen 4-0 Mark Davis
Mark Selby 3-4 Jack Lisowski
- Sports & Recreation
- Jack Lisowski
- Martin Gould
- Tom Ford
- Barry Hawkins