Image source, BBC Sport

This is what's coming up. We'll have live text updates of the afternoon session, as well as the TV pictures, from 14:00 BST.

Tuesday's schedule (seedings and nationalities in brackets)

Afternoon session (from 14:30 BST)

• Mark Allen (4, NI) v Robbie Williams (Eng)
• Mark Williams (6, Wal) 5-4 Si Jiahui (Chn)

Evening session (from 19:00 BST)

• Robert Milkins (16, Eng) 4-5 Pang Junxu (Chn)
• Barry Hawkins (15, Eng) v Ryan Day (Wal)

Paul Curran: The only surprise result for me so far is the Selby result. Other than that, no big names gone yet

Hazel Irvine
Presenter on BBC TV

We're just passing the halfway mark of the first round of this great event in Sheffield.

And of the eight men through to round two, only three of them are seeded players inside the top 16.

No doubt about it, so far, the qualifiers are king and the seeds are scattering.

Image source, Getty Images

Four days in - and we're well in the groove by now, aren't we?

Snooker morning, afternoon and night - beautiful. Dents in the armchair and all that.

But it's not been so comfortable for some of the sport's top stars - with five seeds crashing out of the World Championship already including both of last year's finalists, Luca Brecel and Mark Selby.

Can Mark Williams avoid joining them in making an early exit? He holds a slender lead over last year's shock semi-finalist Si Jiahui - and that match reaches its climax this afternoon.

Michael Emons
BBC Sport at the Crucible Theatre

It's been a brilliant match involving Ding Junhui and Jack Lisowski, just as we expected it to be.

Lisowski, 17th in the world and the toughest first-round draw possible, holds a 5-4 advantage with the fans on table two treated to a great session of snooker.

Ding took the first two frames with breaks of 127 and 60, before the Englishman responded with efforts of 71 and 91 to draw level.

The high standard continued after the mid-session interval with Ding hitting a break of 98, only for Lisowski to take the next to make it 3-3.

Another excellent break, this time 90 from Ding, gave him a 4-3 advantage, but Lisowski claimed the next two, aided by runs of 69 and 67, to take the session.

Michael Emons
BBC Sport at the Crucible Theatre

One of the great stories from qualifying was 52-year-old Dominic Dale reaching the Crucible for the first time in 10 years.

But it has been a painful first session for the Welshman, 40th in the world, as Kyren Wilson produced a superb performance with breaks of 52, 75, 123, 96, 50, 77 and 73 which gave the English 12th seed a commanding 8-1 lead.

He only needs two more frames when that match resumes on Wednesday morning after he produced the most dominant session from anyone so far in this tournament.

Two-time quarter-finalist Dale did have one moment to savour though, with a brilliant 120 clearance.

Joe Perry
Former World Championship semi-finalist on BBC Two

It's living up to the hype. We said it was the tie of the round and it's been fantastic so far.

They're both looking comfortable when they're getting in among the balls - it's going to come down to whose long game is better, who makes the least safety errors.

Because in among the balls there is nothing to choose between them - they're both fantastic. It's just about who is going to get in first, get the first opportunity - and that's down to your safety and your long potting.

Michael Emons
BBC Sport at the Crucible Theatre

Ding Junhui versus Jack Lisowski always looked like being one of the ties of the first round and so it is proving.

Ding, the 2016 runner-up and current world number seven, made a lightning start with a superb break of 127 and then followed that up with a break of 60.

But Lisowski, who only just missed out on qualifying automatically and at 17th in the world is statistically the toughest first-round opponent possible, responded superbly with breaks of 71 and 91 to leave it at 2-2 at the mid-session interval.

Over on the other table, Kyren Wilson stormed into a 3-0 lead against Dominic Dale, helped by a break of 52 in the first and 75 in the third. But Dale, back at the Crucible for the first time in 10 years and at the age of 52, has just knocked in a stunning clearance of 120 to get on the board.

Michael Emons
BBC Sport at the Crucible Theatre

Image source, Getty Images

Elsewhere on Monday, former world champion Shaun Murphy moved into the last 16 with an impressive performance to beat China's Lyu Haotian 10-5.

Murphy, the 2005 winner, was 6-3 ahead after Sunday's first session and won four of the next seven frames to set up a tie with Scotland's Stephen Maguire.

Another former Crucible champion, Stuart Bingham, advanced as he beat 10th seed Gary Wilson - the fifth seeded player to be knocked out after top seed Luca Brecel, fifth seed Selby, ninth seed Ali Carter and 11th seed Zhang Anda all lost in the first round.

Three-time champion Mark Williams began his campaign on Monday afternoon and leads 5-4 against last year's semi-finalist Si Jiahui of China.

World number 16 Robert Milkins has work to do on Tuesday evening as he trails 4-5 to China's Pang Junxu.

Michael Emons
BBC Sport at the Crucible Theatre

Image source, Getty Images

Four-time world champion Mark Selby said he will consider his future in snooker after he lost 10-6 in the first round against Crucible debutant Joe O’Connor.

O’Connor, 30th in the world, held a commanding 7-2 lead after Sunday’s first session, only for Selby to make breaks of 112 and 91 to claim three of the opening four frames on Monday.

A break of 57 in the 14th frame took O’Connor one frame away and he clinched the victory two frames later.

Earlier this month, 40-year-old Selby hinted at retiring and said it is "maybe time to do something else" after losing 10-8 to Gary Wilson in the first round of the Tour Championship.

Selby lost in last year's world final but this was the first time he had been eliminated in the first round since 2018.

He told BBC Two: "I will definitely still review it [my future] because I stopped myself from playing well when I had my chances and I can't keep doing that because it makes me ill and gets me down mentally.

"I will sit down with [wife] Vikki and see what the options are. It will be a big decision but if I carry on playing I need help, probably on the mental side of it, to enjoy the game a bit more."

This is what's coming up today. We'll have live text updates of the afternoon session from 14:00 BST.

Tuesday's schedule (seedings and nationalities in brackets)

Morning session (from 10:00 BST)

• Kyren Wilson (12, Eng) v Dominic Dale (Wal)
• Ding Junhui (7, Chn) v Jack Lisowski (Eng)

Afternoon session (from 14:30 BST)

• Mark Allen (4, NI) v Robbie Williams (Eng)
• Mark Williams (6, Wal) 5-4 Si Jiahui (Chn)

Evening session (from 19:00 BST)

• Robert Milkins (16, Eng) 4-5 Pang Junxu (Chn)
• Barry Hawkins (15, Eng) v Ryan Day (Wal)

Image source, BBC Sport

BBC iPlayer

All times in BST and subject to change

Tuesday 23rd April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Wednesday 24th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Thursday 25th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Friday 26th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Saturday 27th April

Day Session (10:00 – 18:00) – coverage available via BBC One, BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Sunday 28th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Monday 29th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Tuesday 30th April

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Wednesday 1st May

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Thursday 2nd May

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Friday 3rd May

Day Session (10:00 – 18:00) – coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, BBC Four, Red Button, BBC IPlayer & the BBC Sport website.

Saturday 4th May

Day Session (10:00 – 18:00) – coverage available via BBC One, BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:30) - coverage available via BBC Two, Red Button, BBC IPlayer & the BBC Sport website.

Sunday 5th May

Day Session (13:00 – 16:15) – coverage available via BBC Two, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:00) - coverage available via BBC Two, BBC IPlayer & the BBC Sport website.

Monday 6th May

Day Session (13:00 – 16:15) – coverage available via BBC Two, BBC IPlayer & the BBC Sport website.

Evening Session (19:00 – 22:00) - coverage available via BBC Two, BBC IPlayer & the BBC Sport website.

Contributor – BBC IPlayer

Get Inspired
#GetInspired

Snooker, billiards and pool all offer different challenges, but from pubs to clubs to competition, they offer an accessible option for anyone hoping to pick up a cue.

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And a great way to start taking part in snooker is through a local snooker club.

English Partnership for Snooker and Billiards provides a club finder, external to locate your local snooker venue.

To find a club in other areas of the UK please contact the national snooker federations of Scotland, Wales or Northern Ireland.

BBC Sport

World Disability Billiards and Snooker (WDBS) is an organisation that was formed to open up opportunities for players of all disabilities: physical, intellectual and sensory.

WDBS operates as a subsidiary of the World Professional Billiards and Snooker Association (WPBSA) and has held several events in the UK - for more information click here, external.

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