It was not a good day at the office for John Higgins
World champion John Higgins suffered a second-round 5-2 defeat by Mark Williams in the China Open.
Higgins fought back after losing the first two frames, but the Welshman, who has risen to nine in the provisional rankings, made a 108 to secure victory.
Neil Robertson hit a maximum 147 but it was the only frame the Australian won in a 5-1 drubbing by Peter Ebdon.
Stephen Hendry beat Ryan Day 5-0, Mark Allen saw off Stephen Maguire, while Mark Selby fell to China's Ding Junhui.
In the day's other ties, Marco Fu rattled in five successive frames to beat Nigel Bond 5-3, Ali Carter defeated Joe Perry 5-3, and Mark King made a 91 break to eventually beat Chinese wildcard Tian Pengfei 5-3.
While Williams' victory was by no means a shock, Higgins, the provisional number one, will be concerned by his stuttering form with just two weeks to go before he attempts to defend his world crown.
The 34-year-old Scot admitted he needed to improve after his first-round win over Fergal O'Brien and despite breaks of 67 and 93 on Thursday, it was Williams who dominated to come through an enthralling battle.
It brought an end to Higgins' sequence of reaching at least the semi-finals of six consecutive ranking events and the resurgent Williams was delighted.
Williams, who now faces Fu in the quarter-finals, said: "To beat the world champion at any time is difficult so I'm very pleased to do that, especially as I played well all the way through the match.
"John missed a few balls and I capitalised on that and made some good breaks."
Defending champion Ebdon easily came through his clash with Robertson but had to witness the Australian knocking in a maximum break to level at 1-1.
It is the 70th 147 in snooker history and the first achieved since last June and will earn him a £20,000 bonus, plus a probable £2,000 for the highest break prize.
Robertson, who has climbed from ninth to three in the provisional rankings, was disappointed not to make the final eight, but said that his opponent had played "fantastic snooker".
"It's always been one of my dreams to make a 147, especially in a televised ranking event," this season's Grand prix winner added.
"If you make a 147 early in the match, there are lots of emotions and for the next half an hour you are excited, you can't calm down and forget about it, so it's hard to focus on the match.
"In terms of trying to win, it's about the worst thing that can happen - unless you do it in the last frame."
Ebdon will next play Junhui, King faces Carter, while Hendry will be up against Allen, the 24-year-old rising star from Antrim.