Ronnie O'Sullivan has been fined more than £20,000 after a disciplinary hearing into his walk-out at the Maplin UK Championship in December.
O'Sullivan leaves the arena after handing victory to Hendry
The World Professional Billiards and Snooker Association's disciplinary committee ruled he had breached rules by quitting against Stephen Hendry.
The financial penalty comprises £4,050 in forfeited winnings, £5,000 towards the hearing's costs and a £11,750 fine.
O'Sullivan, who attended the hearing, was also docked 900 ranking points.
The former world champion was trailing Hendry 4-1 in the quarter-final of the tournament in York when he missed an attempted pot, shook the hands of Hendry and referee Jan Verhaas and walked out of the venue.
Afterwards, O'Sullivan apologised to spectators and his opponent for his behaviour, which he blamed on "a bad day at the office."
"I wish I could have given Stephen a better game and I'm sorry I didn't stick around to sharpen him up for his semi-final," he added.
"I'm also really sorry to let down the fans who came to see me play - it wasn't my intention to disappoint them and for that I am truly apologetic."
The player's management company 110sport issued a statement saying they were "disappointed" by the panel's decision, and solicitor Leo Martin refused to rule out an appeal against the punishment.
"We regret the outcome of the tribunal given that certain declarations of a sensitive and personal nature were made by the player and by myself on his behalf," he said.
"We would have expected the Association to support their member."