Snooker fans were TWICE reprimanded by the match referee in the same frame during Ronnie O’Sullivan and John Higgins’ World Championship clash.The two legends are battling in the second round at the Crucible – their seventh meeting after their first encounter in 1996 – making it the joint-most frequent match-up in the tournament.O’Sullivan is in pole position to secure his spot in the World Championship quarter-finalsGettySeven-time world champion O’Sullivan leads 6-2 heading into Sunday’s evening session.But despite a dominant first session in Sheffield, he was left frustrated by the antics of one spectator.In the fourth frame, with ‘The Rocket’ leading 2-1, O’Sullivan became the latest victim of mobile phone madness.In the previous round, a noise from a fan’s phone made a noise – resulting in Pang Junxu to walk away from his shot during his defeat to Neil Robertson.But despite repeated warnings for attendees to switch off their phones, some fans just can’t help themselves.Ron-believableUp by 29 points, the ambidextrous O’Sullivan was attempting a shot on the black with his weaker left hand.Though he ultimately pulled up after being distracted by someone in the audience.Visually annoyed, he alerted stewards to the offender by pointing towards the individual.He simply stated: “It was him.”The referee then issued the person a stern telling off, as he snapped: “Can you take the phone down please? It needs to stay down please.”O’Sullivan was preparing to take a shot – only to be distracted by a fanTNT SportsHe walked away from his shot and pointed out the fan to alert match officialsTNT SportsPut off by the incident, O’Sullivan went back to his seat and took a sip of water to compose himself.Speaking on TNT Sports commentary, Dave Hendon said: “It’s unfortunate, I did not see what happened, but something put him off.”He was in a good zone there with his concentration. He does not want to let it annoy him, though.”Sometimes something can put you off, and it can be quite annoying that it happened, it is the last thing you need.”Hendon’s co-commentator – and former world number three Neal Foulds – then quipped: “I bet whoever it is hopes he pots this now.”O’Sullivan did just that by potting the black before producing an incredible 137 break to go two frames up.O’Sullivan went back to his seat as the match referee issued a warning to fansTNT SportsAnd at the start of the fourth frame, the match referee was forced to intervene as he issued a warning to fans after a phone went off following O’Sullivan’s break.The official quickly said: “Just make sure that is switched off, please.”Referencing O’Sullivana and Higgins’ first Crucible match 30 years ago, Hendon remarked: “I will tell you one thing, when they first played here in 1996, mobile phones were far less prevalent than they are now.”It would be nice to think that that would be turned off at some point.”The winner of O’Sullivan and Higgins will play either Robertson or Chris Wakelin for a place in the semi-finals.