Is the famous hoodoo going to be lifted in 2020?
Allen compiled five century breaks, but that wasn’t enough against the Crucible rookie.
The “Magician” couldn’t find the magic touch as he bowed out at the opening hurdle for the third time in five years.
The Scot reached the quarter-final in 2015 when he knocked then defending champion Mark Selby out in Sheffield.
The “Rocket” launched into the second round with a routine opening outing at the Crucible Theatre.
The Australian won the last five frames of his first-round contest on Sunday.
The Welshman looked to be in a spot of bother but won the last seven frames of his first-round encounter.
The 2015 world champion is through to the last 16 after a miniature wobble on Saturday in Sheffield.
The UK government announced on Friday that its pilot scheme allowing supporters to attend sporting events would be suspended.
The world number one remains in the tournament and moves a step closer to breaking the Curse of the Crucible.