World Championship snooker: Ronnie O'Sullivan leads Mark Selby 5-3; Anthony McGill in command against Kyren Wilson

O'Sullivan might still have nightmares about his defeat to Selby in the World Championship final here back in 2014 when surrendering a 10-5 lead, and this latest encounter between two old rivals is already hinting it might go the same way.

After a first session in which both players struggled with conditions - the table playing noticeably slow as heavy contacts became a regular feature of the early action - Selby will feel he has struck gold to only trail by two having failed to register a single break over 50 in eight frames in which he was thoroughly outplayed.

O'Sullivan looked the more assured from the outset and jumped on an early Selby mistake to take the opening frame with the help of a break of 59 and a couple of terrific long pots.

O'Sullivan's razor sharp long game then enabled to him to extend his lead to 2-0, but not before he had missed a black off the spot and Selby had spurned a big chance to counter when failing to make a tricky plant. Another fine long red from O'Sullivan eventually all but put the frame to bed, though he only scrambled over the line as frame-ball blue thought twice before eventually dropping into the middle pocket.

Selby was finally up and running when edging a nervy third frame - one in which both players missed simple pots and suffered any number of bad contacts - but he couldn't capitalise on a good early chance in the next before O'Sullivan put himself back in the driving seat with a run of 85 that required more excellent potting as he fought for control of the cue ball.

When the players returned from the mid-session interval O'Sullivan was straight back into his work and though breaking down on 51, yet another red from distance paved the way for a clearance of 79 that saw him strike the ball with increasing authority as his lead swelled to 4-1.

After Selby had again broken down when afforded another good early chance, O'Sullivan seemed sure to extend his lead further, but his decision to turn down a relatively straightforward red to middle in favour of a tougher pot to the green pocket when on 47 proved costly, the red rattling the jaws and allowing Selby to chalk up his second frame of the night after a short safety joust.

More safety play dominated the start of frame seven, but it was O'Sullivan who got the better of the exchange this time, opening the door for a break of 58 that was much better than it looks on paper given brown, blue and pink were out of commission for much of it.

With O'Sullivan in command at 5-2, he quickly went about finishing the session on a high, but just as he looked sure to hold a four-frame advantage overnight, a luckless split on the reds forced him to take on a tricky pot to the green pocket which missed by a whisker and handed Selby a lifeline.

He needed more than one chance to take that lifeline, but a couple of excellent safety shots allowed Selby to reduce his arrears and he will resume at 2.30 on Thursday afternoon knowing that he has come back from bigger deficits than 5-3 before, most notably against O'Sullivan himself.

McGill makes strong start

Anthony McGill leads Kyren Wilson 6-2 after dominating the first session of their World Championship semi-final at the Crucible.

Wilson, a beaten semi-finalist in 2018, started the match as heavy favourite having claimed the scalp of defending champion Judd Trump in the quarter-finals, but he failed to settle in the early stages as McGill took control of the biggest match of his career.

Any concerns that McGill might be overawed by his first taste of the one-table set-up at the Crucible were soon quashed as the Scot opened up with a handsome run of 83 to take the early initiative.

1-0 soon became 2-0 when McGill added a break of 78 in the following frame before Wilson spurned a glorious opportunity to get a foothold in the match in frame three, the Kettering potter responding to McGill's initial break of 53 with 55 of his own before breaking down with the winning line in sight and allowing his opponent to stretch his lead to 3-0.

Wilson finally found his stride when winning frame four thanks to a hand of 50 but two visits for McGill in frame five were enough to see him reestablish his three-frame advantage and ensure he couldn't lose the session.

When he followed up with a break of 69 in the sixth frame McGill was now certain of finishing the session in front, though he was left frustrated when missing a blue in frame seven that would have surely extended his lead to 6-1.

In the end, Wilson held his nerve to reduce his arrears to 5-2 but McGill was soon back in the box seat as he rounded off an impressive afternoon's work with a break of 92 that ensured he will hold a 6-2 lead when play resumes on Thursday morning.

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