Even the greats are victims to their emotions at times, and proved as much after showing a short fuse in Sheffield. The four-time world champion has a reputation as one of the cooler customers on the World Tour, though he didn't always look it as he exited this year's on Thursday.

Selby, 41, never truly looked in control of his match against Ben Woollaston and led for just a single frame en route to a 10-8 defeat. And it was at the conclusion of the 13th frame that he put his temper on full display when he conceded by flinging the yellow across the table before heading in for the interval.

Woollaston, 37, took a 7-6 lead as a result and edged four of the last six frames to bag one of the biggest wins of his career to date. And was in a state of disbelief by what he had witnessed between the pair.

TNT Sports commentator Dave Hendon highlighted just how rare the show of emotion was as he said: "Look at that reaction from Selby, he’s not happy. You don’t see that often from the master of brinkmanship."

However, O'Sullivan offered some sympathy to his snooker rival when he joined in the commentary at the interval. And he suggested the frustrations may have come down to Selby's hardware.

"We don’t know if he’s got a new tip on, but if he has then it can be a kind of excuse," he said. "We don’t know but I am assuming it is as there have been so many mistakes from him.

"When he left that yellow over the pocket it was a complete mis-hit, which he never, ever does. When your tip is not right, your confidence goes, you just start to lose confidence in your cue and tip, and it can just get worse and worse."

When pressed for his reaction to Selby throwing said yellow, O'Sullivan added: "He’s annoyed, he’s frustrated, he’s just angry. You never normally see that with Selby."

And the baize legend is right given 'The Jester from Leicester' is widely known for his calm under chaotic conditions. But even his fuse appeared to blow en route to what will go down as one of his most surprising defeats on a stage of this magnitude.

Seven-time world champion O'Sullivan is one who would know a thing or two about not hiding his emotions around the table. 'The Rocket' returned to the Crucible this month having not played since January when he snapped his cue in frustration at the Championship League.

The 49-year-old withdrew while trailing Robert Milkins 3-2 at the Leicester Arena. And he confirmed his exit with a bang (literally) after smacking his cue against the table when a series of shots failed to go his way.

Woollaston came into their clash ranked 44th in the and wasn't given good odds of advancing. Instead, Selby became the sixth seeded player to crash out at the Crucible in the opening round.

Fellow Leicester native Woollaston will advance to face China's Si Jiahui in the next round of the competition. And he'll hope calmer heads once again prevail in his efforts to upset another contender seeded higher than him.