Ronnie O'Sullivan found himself at the centre of another controversy at the World Championship when he put chalk down on the table during the first session of his quarter-final against Stuart Bingham at the Crucible, where Judd Trump took a step closer to the semi-finals as he opened up a commanding 12-4 lead over Ding Junhui.
Five-time champion O'Sullivan – who earlier in the tournament had played some of a frame in his socks and was then warned about his behaviour following a hand gesture in the second-round match against Matthew Stevens – had just reeled off the second century break to level at 2-2 before causing a stir when he placed his chalk on the baize while lining up a shot.
It is a move which is deemed against competition rules if any object is used to measure gaps or distances, and therefore subject to a foul with a seven-point deduction.
However, referee Terry Camilleri failed to call the penalty and Bingham did not raise the matter either, with O'Sullivan going on to complete his 87 break and take the frame.
It remains to be seen what World Snooker officials will make of any review the incident, which was highlighted in match analysis by television pundit Ken Doherty.
Bingham, though, did not let the issue unsettle him, as the Essex potter, ranked number 10 in the world, won the remaining three frames to take a 5-3 lead, with the match set to resume on Wednesday afternoon.
Trump, meanwhile, was in fine form as he dominated his quarter-final match against third seed Ding.
The 25-year-old world number six, who had defeated O’Sullivan at the World Grand Prix final, never looked back after storming into a 4-0 lead on Tuesday’s early session, which he extended following a break of 108.
Ding finally got off the mark when he won back-to-back frames to trail 6-2 at the end of the afternoon.
But that mini-revival was soon halted on the resumption following another century from the Bristol man, who was runner-up to John Higgins in the 2011 World Championship final.
Trump chalked up a blistering 127 break before wrapping up the evening session with another century to stand one frame away from a place in the semi-finals again when play continues on Wednesday morning.
Qualifier Anthony McGill ended the hopes of defending champion Mark Selby in round two and was putting up another battle against former winner Shaun Murphy.
With Tuesday’s first session locked at 4-4, McGill opened up with a 137, but Murphy quickly hit back as the players went into the mid-session interval again all square.
Murphy, who claimed the Word Championship title a decade ago having come through qualifying, looked refreshed, scoring 127 and then moving 8-6 ahead as attention centred on the remaining table late into the evening session.
‘The Magician’, though, pressed on under the spotlights, with 75 enough to clinch the next before the Scot made the most of an opening in the final frame to chalk up 86 and, perhaps crucially, reduce the deficit to 9-7.
The remaining quarter-final between Neil Robertson and Barry Hawkins will also resume on Wednesday, starting at 10am.
Australian Robertson, world champion in 2010, will be looking to halt the momentum of Hawkins, who won four frames in a row to lead 5-3 as the Kent potter aims to go one better than when beaten at the Crucible by O’Sullivan in the final two years ago.
