It has taken 12 frames, but Mark Selby has just made his first half-century of the final. Is this the start of a sensational fightback?

If you think Mark Selby may be heading for defeat in Sheffield, did you know the heaviest loss in a World Snooker Championship final came in 1989 when the number one seed Steve Davis defeated John Parrott 18-3?

George Riley
BBC Radio 5 live at the Crucible

"I'm not saying it would necessarily make a difference but both Neil Robertson and Mark Selby last night called for a rest day before finals."

Do you agree with George? Would a rest day make any difference? Is Selby burnt out? Let us know on Twitter, using #bbcsnooker.

Nick Comber:, external Selby is already a broken man. Very obvious mistake to not pot to the green and get a good snooker there.

Martin Teasdale:, external Even if he didn't equal or surpass Hendry's seven world titles I would say Ronnie is definitely the greatest of all time.

Dan:, external Selby's highest break has been 42, nowhere near as good enough to compete with Ronnie.

Of the four matches O'Sullivan has played in this year's tournament, three have been won comfortably with 10-4, 13-3 and 17-7 victories against Robin Hull, Shaun Murphy and Barry Hawkins respectively.

Nothing has really happened yet in the 12th frame. As soon as it does, I will tell you.

We asked earlier if Ronnie O'Sullivan was the greatest snooker player of all time?

Here is some early reaction.

Image source, Getty Images

Paul Fisher:, external No, the greatest player was Alex Higgins, flawed, unpredictable, unreliable, yes, but the snooker genius of all time.

Dom Blampied:, external Hendry has the best record of all time, but O'Sullivan is the greatest player ever.

Stephen Hendry
Seven-time world champion on BBC TV

"Selby is just not thinking straight. Pot the red, black and then yellow and you have the easiest snooker in the world. He is not thinking straight. Mark looks down, he's not played with any authority here."

This is starting to look like it is going to be a very one-sided final. It has not been the best start to the evening session and the snooker has been patchy at best.

But this is the true test of a champion. Selby has been the world number one, he has won the Masters twice and is regarded as one of the toughest match players out there. He will need to dig deep to pull this one out of the fire.

Ronnie O'Sullivan 8-3 Mark Selby (67-27, O'Sullivan 63 break)

Image source, AFP

Tim Ferwood:, external Stephen Hendry is the greatest player of all time, but if O'Sullivan keeps up his current form, he'll surpass Hendry in no time.

Rob Keegan:, external Selby obviously played all his best snooker last night. Ronnie wins this easily now.

Andrew Foley:, external This Ronnie O'Sullivan chap is not bad for a fella ranked number 33 in the world.

Ronnie O'Sullivan makes a break of 63 and Mark Selby needs two snookers to avoid going 8-3 behind.

He had led this frame 23-0 but a problem red, which rattled and rattled in the jaws of the pocket but would not fall, gave his opponent another chance.

Six-time world champion Steve Davis has experienced the highs and lows of snooker. But how did he get through those tough times in matches?

"You get some moments when the wheels fall off and you have to re-group back in the dressing room," says Davis.

"That is the fascinating thing about these multi-session matches. You can go through ups and downs, even in the mini-sessions. It is great to have someone on your side to bring you down to earth and help you out.

"That is when the sports psychologist or good friend can help you out, because it is very hard to deal with it when it is going badly. Even if it is going well, just to calm down, think about something else to take your mind off it."

Image source, Getty Images

Gloucester potter Robert Milkins,, external who lost on a re-spotted black in his Championship qualifier against Michael Wasley, writes on Twitter: Bored of this, turning over. Can't remember watching a worse final, nothing happening.

In the 1981 final between Steve Davis and Doug Mountjoy, Davis led 49-48 and only the blue, pink and black remained.

After 31 shots with the black on the edge of the pocket and the blue alongside, the referee gave the players a further three shots to resolve the situation, and after no resolution was reached, the frame was reset after 41 minutes.

Philip Maher:, external Ronnie's fitness regime has to make a difference in these longer World Championship matches.

Rupinder Bedi:, external Ronnie on song is perhaps the greatest sportsman ever.

Joelle:, external Perfect Bank Holiday relaxation in front of #bbcsnooker. Hoping Selby can catch up tonight and make things interesting.

That's high praise from Rupinder. Do you agree? Firstly, let's start with snooker. Is O'Sullivan the greatest player of all time? Let us know. #bbcsnooker on Twitter is the place to make your arguments.

We have just seen snooker's equivalent of a false start. Referee Brendan Moore, officiating in the world final for the first time, has to re-rack the balls as the players decide to start the 11th frame again.

When we get under way again Selby smashes a shot at a corner pocket, it misses, bounces off three other reds and one of them goes in. Could that be the spark and piece of luck Selby needs to get back into the match?

Remember, we want your thoughts and observations on the match. Is there any way back for Selby?

Is O'Sullivan heading for a sixth world title? Is Selby feeling the effects of his gruelling semi-final against Neil Robertson?

What does Selby need to do to stop O'Sullivan? Let us know on Twitter, or leave a message on the BBC Sport Facebook page. , external

Stephen Hendry
Seven-time world champion on BBC TV

"Ronnie is prepared to do what he can to win it and that's what he has focused on in the last couple of years."

It is 7-3 to O'Sullivan. Selby's efforts in fighting back from 3-0 down seem to have all been wasted now. O'Sullivan, helped by a break of 52, moves four frames in front for the first time in the match.

Ronnie O'Sullivan 7-3 Mark Selby

It is an epic battle for safety supremacy at the moment. O'Sullivan holds a 22-point lead with 18 on the table. Sometime soon it is either going to be 6-4 or 7-3.

We are still in business in the 10th frame. With five balls left, Selby has to play safe after compiling his highest break of the match so far with an effort of 42.

Surprising that the world number three has yet to make a break of at least 50 after 10 frames of the World Championship final. O'Sullivan leads this one 57-42 with green, brown, blue, pink and black still left on the table.

You get the feeling this is one of those must-win situations for Mark. If he were to fall 7-3 behind then it would be a long way back.