The Scot reached the quarter-final in 2015 when he knocked then defending champion Mark Selby out in Sheffield.
Anthony McGill is through to the last 16 of the 2020 World Snooker Championship after a dramatic 10-9 triumph over Jack Lisowski on Monday.
From 2-1 behind, the former Indian Open champion was always in front but was almost caught at the very end as his seeded opponent made a late charge.
McGill won four frames on the spin to lead 5-2, but Lisowski took the last two of the first session and the opening frame of the evening’s bout of play to restore parity.
Then, with the scores locked at 6-6, McGill made a surge for the winning line with breaks of 70, 67, and 51 bringing him within one frame of victory.
Lisowski dug deep and retrieved the deficit with contributions of 65 and 102, his second century of the match, before levelling again to force a decider.
A tense finale was a fitting conclusion, ultimately ending with McGill rattling in an excellent long blue followed by the last pink for glory.
Once as high as number 13 in the world rankings, Anthony McGill has suffered in recent seasons and is now languishing outside the top 32.
However, the 29 year-old demonstrated some form in the qualifiers, in which he had to win two ties to advance to the venue stages, and he’ll next face either Mark Allen or Jamie Clarke for a quarter-final berth.
What a match to end the day. A thriller between Anthony McGill and Jack Lisowski at the Betfred World Snooker Championship.
— BETFRED (@Betfred) August 3, 2020
Elsewhere on the fourth day of action at the Crucible Theatre, Ronnie O’Sullivan made light work of his first-round task – thrashing Thepchaiya Un-Nooh 10-1 in record-breaking time.
It was much more laborious for Yan Bingtao, as the Chinese 16th seed eventually stumbled into the second round with a protracted 10-7 triumph against Elliot Slessor.
Yan led 9-2 but found the winning frame an elusive one to find with errors escalating and nerves creeping into his psyche.
Slessor took advantage for a spell, but he was ultimately left with too much to do as the 20 year-old 16th seed advanced to set up a meeting with world number one Judd Trump.
Two other fixtures reached their halfway points as well, with Mark Selby 5-4 in front of Jordan Brown and Shaun Murphy in a spot of bother courtesy of a 6-3 overnight deficit to Noppon Saengkham.
Those encounters will finish on Tuesday, with the likes of Tour Championship finalists Allen and Stephen Maguire entering the fray.