The Rocket, 48, was level at 6-6 with Stuart Bingham after their opening four frames on Wednesday.
ALL THE LATEST FROM THE WORLD SNOOKER CHAMPIONSHIP 2024
3
3
And 1991 world champion Parrott, 59, noticed a small adjustment made to O’Sullivan’s waistcoat after he returned to the table.
The two sponsorship logos on his clothing, Cazoo and 9club, had been swapped around during the break, something that was not missed by the experienced Parrott.
The BBC commentator said: “Those of you that are eagle-eyed might have spotted he’s swapped the logos around on his waistcoat as well.
“That must have been done in the mid-session because one of them was annoying him.
“It’s on the other side now. It kept catching on his waistcoat as he was taking the cue back.
“Just annoying sometimes with something like that happening, the game’s tough enough.”
O’Sullivan went on to produce breaks of 79 and 84 to take command of the quarter-final, opening up an 8-6 lead.
But Bingham came roaring back as he took the final two frames to leave things all square at 8-8 ahead of the final session.
CASINO SPECIAL – BEST CASINO WELCOME OFFERS
Snooker icon O’Sullivan is bidding to claim a record eighth world title at the Crucible.
Beating Bingham would see him earn a record-extending 14TH semi-final spot, with Welsh qualifier Jak Jones awaiting the winner.
Jones produced one of the biggest shocks of the tournament on Wednesday afternoon, clinching a 13-9 victory over 2019 champion Judd Trump.
3