Halo World Championship
Venue: Crucible Theatre, Sheffield Dates: 19 April to 5 May
Coverage: Watch live on BBC TV, BBC iPlayer, BBC Sport website and app; live text coverage of selected matches; updates on BBC Radio 5 Live
Debutant Lei Peifan stunned defending champion Kyren Wilson by fighting back from 6-2 down to triumph 10-9 as the 'Crucible curse' struck again in the first round of the World Snooker Championship.
Wilson becomes the 20th player to succumb to the so-called curse, with no first-time winner able to retain the world crown since the tournament moved to Sheffield's Crucible Theatre in 1977.
The chances of an upset had looked slim heading into Saturday evening's session, despite Lei winning the final frame of their morning session to trail 6-3.
However, the 21-year-old from China, who had to win two qualifying matches just to reach the televised stages of the tournament, reeled off another six consecutive frames once play resumed.
Lei, who won the Scottish Open in December, knocked in pot after pot as he crafted six half century breaks and scored 544 points during that burst to move on to the cusp of victory.
In contrast Wilson, who has claimed four ranking tournaments this term, looked completely out of sorts and managed a meagre 44 points until he stopped the rot in the 16th frame with his second century break of the match.
The 33-year-old Englishman cleared up to pinch the 17th frame after Lei broke down on 60 and then made a half century of his own to draw level at 9-9.
But the world number 39 held his nerve and sealed a famous victory with a break of 66 in the decider.
Lei, one of a record 10 Chinese players in this year's first round, will now face either Jak Jones - the player Wilson beat in the 2024 final - or former UK Championship winner Zhao Xintong.
World number 14 Xiao Guodong is in control of the other match that got under way on Saturday morning.
Xiao and Matthew Selt made two century breaks apiece in the opening nine frames, but the Chinese player will take a 7-2 advantage into Sunday's concluding session.
Three-time former champion Mark Williams is 5-4 ahead of China's Wu Yize.
The Welshman won the opening three frames but was then forced to watch on as Wu constructed superb breaks of 120 and 136, as well as two half-centuries to edge 4-3 ahead.
Williams took the final two frames of the session, with that match scheduled to be played to a conclusion on Sunday afternoon.
Barry Hawkins also established a slender 5-4 lead over Iran's Hossein Vafaei.
England's Hawkins crafted three half centuries, while Vafaei's break of 123 was arguably the highlight of a match that concludes on Sunday evening (19:00 BST).
Meanwhile, 2010 world champion Neil Robertson is in danger of an early exit.
The Australian, who failed to qualify for last year's tournament but is now back into the world's top 10, trails England's Chris Wakelin 7-2.
Wakelin opened the match with a 108 break and the world number 20 later reeled off four frames in a row to lead 6-1.
Robertson knocked in a break of exactly 100 to halt that run, but Wakelin took the ninth frame - which lasted close to 55 minutes - to establish a healthy lead before Sunday's deciding session.
10:00
Kyren Wilson 6-3 Lei Peifan
Xiao Guodong 7-2 Matthew Selt
14:30
Neil Robertson 2-7 Chris Wakelin
Mark Williams 5-4 Wu Yize
19:00
Kyren Wilson 9-10 Lei Peifan
Barry Hawkins 5-4 Hossein Vafaei