World Championship snooker: Jamie Clarke shocks Mark Allen; Noppon Saengkham beats Shaun Murphy; Mark Selby through

Despite boasting such an impressive CV, Allen has yet to really feel at home in Sheffield and will head back to Northern Ireland on the back of his second early Crucible exit in as many years.

To Clarke's credit, he held himself together wonderfully well having started the evening 5-4 behind before surging into a 9-7 lead and then watched Allen close to 9-8.

Clarke was the recipient of a number of unforced errors from his more experienced opponent who despite making five centuries in the match, missed any number of simple pots and continually failed to close out frames having built up healthy leads.

Proceedings began with a bang as Allen raced into a 2-0 lead in the morning courtesy of two fabulous century breaks (136 and 105) before Clarke gave the first sign he wouldn't be intimidated by responding with a brilliant total clearance of 136.

When Clarke somehow pinched frame four having needed three snookers, the Welshman would have rightly been thrilled to level the scores but two more centuries from Allen (122 and 104) allowed him to inch back in front at 4-3.

The final two frames of an engrossing morning session were shared to ensure Allen had little breathing space when play resumed in the evening though a run of 105 in frame 10 - his fifth century of the match - extended his lead to 6-4 and apparently put him on course for the second round.

Clarke had other ideas, however, winning four frames on the bounce thanks to well-taken contributions of 53 and 80, some admirable fighting spirit and a few gifts from his opponent.

Allen did show some fight of his own by claiming two of the next three frames to reduce his arrears to 9-8 but Clarke was always on the front foot in frame 18 and try as he did, Allen was powerless to prevent another World Championship bid ending prematurely.

Sorry Murphy sunk by Saengkham

Former champion Shaun Murphy bemoaned "the worst two days of my snooker years" after crashing out of the World Championship in a 10-4 defeat to Thailand's Noppon Saengkham.

Saengkham exploited a series of uncharacteristic errors from Murphy as he built on a 6-3 overnight advantage to become only the third Thai player to win a match in Crucible history.

Afterwards Murphy stressed his performance had not been affected by the recent sudden death of his former manager and mentor Brandon Parker, whose funeral he attended in the Algarve last month.

Murphy told BBC Sport: "I was very much below par across the whole match - probably the worst two days of my snooker years came together at the worst possible time.

"My form has been good this season with two titles and other finals, so this was a shock to me.

"And I can say that the build-up to the tournament had no impact. I came here wanting to honour Brandon Parker's memory.

"You dream of winning the title and dedicating it to him and things like that. But I would never dishonour him by saying that has caused me a problem."

Saengkham, who admitted he barely slept on Monday night, showed no sign of nerves as he produced breaks of 53 and 63 to extend his advantage to five frames.

A rare missed red enabled Murphy to temporarily reduce the deficit, but further breaks of 60 and 74 either side of the mid-session interval saw Saengkham ease home.

Saengkham estimated up to one million people will have watched the match in a country whose appetite for snooker was largely cultivated by the exploits of former world number three and two-time Crucible semi-finalist James Wattana.

He said: "James taught me everything - how to come here and speak the language. He taught me how to get through because for an Asian player to come to the UK is difficult.

"I felt a lot of pressure but I just tried to concentrate on the table and not think about all those people watching me.

"For the last three or four days I have turned my phone off and not done anything on the internet. If I turn my phone back on it will be too much pressure with all the messages."

Selby fails to convince in opening win

Saengkham will face Mark Selby in the second round after the latter struggled to a 10-6 win over qualifier Jordan Brown.

Selby claimed Crucible glory three times between 2014 and 2017, but has found things much tougher in Sheffield more recently and he was a long way from his best here.

Brown would have been kicking himself having ended Monday night's first session 5-4 behind and he was left to rue more missed opportunities when the match concluded on Tuesday, particularly in frame 14 when in first and apparently well set to level the scores.

However, another spurned chance from the Antrim 32-year-old let Selby off the hook and once establishing an 8-6 advantage, the latter cut a much happier figures as he claimed the next two frames to close out the match.

Gould blitz leaves Maguire on the ropes

Martin Gould was contemplating retirement only a few months ago but he produced one of the performances of the tournament so far, making four centuries in a dazzling display that saw him build a 7-2 lead over Stephen Maguire.

The latter would have arrived in Sheffield with genuine title aspirations having claimed the valuable Tour Championship recently but he had no answers to an inspired Gould who added breaks of 57, 77 and 83 to his four tons.

Gould had given sign that he was nearing a return to his best form when beating Graeme Dott in qualifying and he will only require three more frames to book his place in the second round when that match concludes on Wednesday afternoon.

Barry Hawkins looks set to continue his love affair with the Crucible after he kicked off his challenge by taking a 7-2 over Alexander Ursenbacher after the first session of their match.

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