Mark Selby crashed out in the opening round of the Welsh Open following a 4-3 defeat by Liam Highfield on Wednesday.
The reigning World champion is a three-time winner of Home Nations titles, with only Judd Trump (four) capturing more since the establishment of the series in the 2016-17 season.
Selby claimed his maiden ranking crown at this event in 2008, while he was runner-up to Ding Junhui four years later.
But the Jester, who recently lifted the lid on his ongoing battle with depression, fell at the first hurdle this time around against world number 40 Highfield at Celtic Manor Resort.
The left-hander took an early 2-0 lead – snatching the second frame on the black from 65-0 down – but the world number one hit back with breaks of 50, 73 and 115 to turn the contest on its head at 3-2.
Nevertheless, Highfield held his nerve with a run of 74 forcing a decider, in which a lovely 92 clearance from 40-18 down saw him prevail.
Selby was not the only seeded player to bow out in a deciding frame. UK champion Zhao Xintong suffered a similar feat against home favourite Jak Jones, as did Mark Allen and Stuart Bingham against Joe Perry and Elliot Slessor respectively.
Meanwhile, five-time champion John Higgins suffered his fourth defeat in five meetings with Ali Carter, who hit breaks of 141, 87 and 81 as he inflicted a 4-2 defeat.
Elsewhere, Ronnie O’Sullivan recovered from 2-1 down to see off Lukas Kleckers 4-2, while Judd Trump overcame Si Jiahui by the same scoreline.
Kyren Wilson produced back-to-back centuries of 136 and 102 to complete a commanding 4-0 whitewash of Li Hang, as Yan Bingtao also reeled off four frames without reply against Zhao Jianbo.
Shaun Murphy went close to compiling the seventh maximum break of his career during a 4-1 victory over Anthony Hamilton – missing a tricky final red – while Neil Robertson and Barry Hawkins also claimed successes by that margin against Graeme Dott and Ashley Carty respectively.
Welsh Open Snooker 2022 Results
Wednesday March 2
Lu Ning 2-4 Matthew Stevens
Graeme Dott 4-1 Jamie Clarke
Kyren Wilson 4-0 Li Hang
Stuart Bingham 3-4 Elliot Slessor
Zak Surety 1-4 Ryan Day
Shaun Murphy 4-1 Anthony Hamilton
Ronnie O’Sullivan 4-2 Lukas Kleckers
Ricky Walden 4-1 Noppon Saengkham
Zhao Xintong 3-4 Jak Jones
Barry Hawkins 4-1 Ashley Carty
Yan Bingtao 4-0 Zhao Jianbo
Mark Selby 3-4 Liam Highfield
Mitchell Mann 0-4 Matthew Stevens
Neil Robertson 4-1 Graeme Dott
Jimmy Robertson 4-2 Fergal O’Brien
Kurt Maflin 1-4 Scott Donaldson
Zhang Anda 4-2 Yuan SiJun
Si Jiahui 2-4 Judd Trump
Mark Allen 3-4 Joe Perry
John Higgins 2-4 Ali Carter