Defending champion Ronnie O'Sullivan has pulled out of the Masters.
O'Sullivan won the title last January by defeating Ali Carter 10-7 in the final and is the all-time record winner with eight victories.
However, 'The Rocket' won't be competing this year at Alexandra Palace in London on "medical grounds", a statement from the World Snooker Tour said on Friday.
O'Sullivan had been due to play fellow legend John Higgins in the first round on Sunday, but his place will now be taken by Neil Robertson at the tournament which runs until January 19.
The news follows reports seven-time world champion O'Sullivan threw his cue in the bin on Thursday after withdrawing from snooker's Championship League.
The 49-year-old played four matches in the competition on Wednesday, losing three of them, and seemed to have trouble with the tip on his cue.
He then whacked his cue on the table in frustration and lashed the white ball into a group of reds during his defeat to Robert Milkins on Thursday morning before pulling out of the non-ranking event ahead of a scheduled afternoon meeting with Carter.
A statement from the World Snooker Tour read: "Neil Robertson has replaced Ronnie O'Sullivan in the draw for the upcoming Johnstone's Paint Masters.
"Last year's champion O'Sullivan was due to face John Higgins in the opening match on Sunday afternoon, but has withdrawn on medical grounds."
