Ronnie O'Sullivan could be set for a fine after playing with no shoes on for some of his 2015 World Snooker Championship opener against qualifier Craig Steadman on Tuesday.
In terms of the scoreline, five-time champion O'Sullivan enjoyed a relatively comfortable time of it, emerging from the first session of the encounter - that had begun with him making a century break - with a 10-3 victory over Crucible debutant Steadman.
But the world No.2, who suffered a broken ankle towards the end of last year, appeared in discomfort due to his footwear at one point and opted to remove his shoes, briefly playing on in his socks.
He subsequently borrowed a pair of shoes from tournament director Mike Ganley and put them on, but the Press Association reports that the World Professional Billiards and Snooker Association will look into the matter to consider whether it constitutes a breach of its rules about members' dress code, which could see O'Sullivan handed a fine.
Meanwhile, two-time finalist Ali Carter, given the all-clear from lung cancer in December, made a winning start to his campaign as he completed a 10-5 win over veteran Scot Alan McManus.
Carter finished the job from a 6-3 overnight lead to set up a last-16 meeting with Australia's 2010 champion Neil Robertson, the world No.4.
"I didn't feel as if I played great, but I competed in all departments and won quite convincingly in the end," Carter said. "I have some good memories here - the only thing I have left to do is win it, and that's what I'm here to do."
Earlier, Ding Junhui admitted he forgot he was on course for a maximum break during his 10-7 win over Mark Davis which secured his place in the second round.
Ding was 5-3 down at the Crucible and was on a break of 96 when, to the amazement of the audience, he played for the blue ball and ignored the black.
"It doesn't happen until I know it's a 147," he said. "I just kept scoring and trying to make centuries and heavier breaks and put him under pressure.
"Until the last red I potted and then I heard the noises and looked at the scoreboard. I tried to make it difficult for myself, and that's it!"
As his mistake dawned on him, Ding sunk his head into his hands and paused before forcing a smile and carrying on.
"I just make centuries. I didn't know, really," he said. "I didn't even think about playing for a 147 but to keep going and keep potting the balls."
The evening session saw Northern Ireland's Mark Allen secure his second-round place by wrapping up a 10-3 win over Wales' Ryan Day.
Allen had built up a 6-3 lead from the first session earlier in the day and swiftly finished the job later on to progress to an encounter with world No.5 and 2013 finalist Barry Hawkins.