Ronnie O'Sullivan kept his composure in the arena but lost it in a television interview backstage after firing three brilliant centuries to knock Mark Williams out of the World Championship.
The three-time champion took offence at being described as his 'own harshest critic' in a BBC interview and warned he would walk out if that point was ever put to him again.
But considering the Crucible audience were on their feet to acclaim his brilliant 13-10 win against Williams, while O'Sullivan saw little to enjoy from the performance, it hardly seemed like the grotesque assessment it was clearly taken to be.
"If someone says that to me again I'm going to stop the interview," O'Sullivan told interviewer Rob Walker.
"I'm fed up with hearing that."
"When you play poor snooker, you play poor snooker."
"I don't listen to people saying I'm my own harshest critic."
"You don't know what you're talking about."
O'Sullivan claimed 'sheer panic and desperation' inspired him to produce the five-star snooker which carried him past Williams.
Breaks of 53, 104, 75, 111 and 106 came from the cue of O'Sullivan in the deciding session, and Welshman Williams later said of his conqueror: "Everything about his game is spot on. The only person who can beat him in this World Championship is himself."
In the press conference which followed the BBC interview, O'Sullivan played down his chances of adding to the world titles he won in 2001, 2004 and 2008.
"For a change I managed to put a few decent frames together, to my surprise," he said.
"Out of panic and desperation I managed to find a bit of form."
"I wouldn't say it was really flowing."
"There's no point me getting carried away because over the years I've thrown two or three world titles away."
"I know why but I can't cure it. I can't afford to let myself get confident."
"I've played too many up-and-down games over the years to even think about getting excited anymore."
"I've managed to win most of my tournaments not playing well so I can do it but it'll be a lot easier on the nerves if I can find a bit of form, a bit of rhythm and just keep applying pressure to the opponents."
Williams had looked favourite for the match when he led 8-6, but then O'Sullivan's form kicked in.
Williams said: "You've got to take your hat off to him. Some of the clearances and the shots he was pulling off, he was just outstanding."
Mark Selby awaits O'Sullivan in the quarter-finals, after completing a crushing 13-5 win against Stephen Hendry this evening.