Defending champion Judd Trump was knocked out in the first round of the International Championship by Alan McManus in Chengdu, China.
The world number three, 24, lost 6-5 to Glaswegian McManus, 42, ranked 48th.
There were further upsets as world number five Stephen Maguire and sixth-ranked Shaun Murphy also departed.
Maguire lost 6-3 to world number 91 Kyren Wilson and Murphy was beaten 6-4 by world number 35 David Gilbert, but Neil Robertson and Mark Selby both won.
Australian Robertson, the world number one, overcame Englishman Alex Davies 6-4 while number two Selby whitewashed Scot Jamie Burnett 6-0.
Ding Junhui, up to four in the world after winning the last two ranking events, overcame fellow Chinese player Cao Yupeng 6-5 in a final-frame decider.
But wildcard entry Jimmy White was beaten 6-2 by world number seven Barry Hawkins.
Trump, who also lost in the first round of his last ranking event, at the Shanghai Masters last month, told World Snooker: "He [McManus] played well and that's just the way it's going at the moment.
"I haven't had a great season so far. Everyone seems to play well against me. A bit of luck here and there can make the difference and there were a couple of times today when Alan got away with bad shots, and I didn't.
"I prepared well for this tournament and tried my best so I'm disappointed to lose."
McManus said: "I was behind a few times but there was never more than a frame in it. There was a lot of good stuff, Judd played well in patches and I was hanging on and chasing him.
"I was glad to get a couple of chances in the last frame."