Amateur James Cahill is five frames away from producing one of the all-time sporting shocks at the Crucible.

Cahill, the first amateur to play at the World Championship, leads Ronnie O’Sullivan 5-4 at the halfway stage of their first-round match in Sheffield.

World number one O’Sullivan looked out of sorts throughout and must pick his game up when play resumes on Tuesday morning.

James Cahill is giving Ronnie O'Sullivan a game in Sheffiel
James Cahill is giving Ronnie O’Sullivan a game in Sheffield (Nigel French/PA)

Cahill rarely looked in awe of his fancied opponent, who is chasing a sixth world crown, and came back after trailing 2-1, 3-2 and 4-3 before winning frame nine.

John Higgins, hunting a fifth title, is safely through to round two after beating Mark Davis 10-7, rattling in breaks of 100, 135 and 132 along the way.

Three-time champion Mark Selby hit back from 5-1 down in the morning session to finally triumph 10-7 against Zhao Xintong.

The Jester from Leicester had battled back to be 5-3 down and continued to recover, eventually hitting three century breaks and five over 50 in his victory.

Selby avoided another first-round exit in Sheffield have also bowed out early at the UK Championship and at other notable events during the campaign, including last month’s Players Championship.

While Selby was toiling in the morning, Shaun Murphy condemned Luo Honghao to the heaviest defeat in tournament history.

In winning 10-0, Murphy became just the second man to record a Crucible whitewash, while Luo’s 89 points were a record low.

Shaun Murphy made light work of
Shaun Murphy made light work of Luo Honghao (Richard Sellers/PA)

Murphy now faces Neil Robertson and hopes he can make the most of his late-season form.

“After the season I have had, never in my wildest dreams did I think I could come here and win 10-0,” Murphy told World Snooker’s official website.

“This has been the worst season of my life, I have been in a daze. Yesterday I felt like Shaun Murphy again. In a way I’m looking forward to this season being over, but while I’m here I’ll give it my best.”

David Gilbert, competing as seed for the first time, is 6-3 up overnight against Joe Perry.