Defending champion Judd Trump and world champion Kyren Wilson have both been eliminated from the World Open in Yushan.
Trump, the world number one who had won the previous two editions of the tournament, was defeated by fellow Englishman Joe O'Connor.
Wilson suffered a dramatic loss to China's Zhou Yuelong, despite a valiant comeback attempt.
The high-profile exits continue a trend of major upsets at this year's event in China.
Judd Trump has crashed out of the World Open in surprise circumstances
PA
Both players had entered the tournament as favourites but failed to progress beyond the last 32.
O'Connor produced a stunning performance to end Trump's 16-match winning streak in the tournament.
The Leicester man raced into a 2-0 lead with breaks of 64 and 89.
Trump managed to level at 2-2, but O'Connor responded with breaks of 51, 69 and 113 to secure a famous victory.
"Any win over someone of Judd's calibre makes you feel over the moon," said O'Connor after his triumph.
"I just enjoy being out there against the best in the world, luckily for me this was my day and I won."
The world number 39 will face Michael Holt in the last 16.
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Zhou's victory over Wilson was equally dramatic, with the Chinese player racing to a 4-0 lead with impressive breaks of 120, 73, 54 and 109.
Wilson, showing the resilience of a world champion, fought back spectacularly.
The Warrior compiled runs of 118, 100 and 64 to force a deciding frame.
However, Zhou held his nerve when it mattered most. A break of 71 in the decider secured his place in the last 16.
The 27-year-old Chinese star now faces a tough challenge against John Higgins in the next round.
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Kyren Wilson fought back valiantly but it was not enough
PA
These upsets follow other major shocks in the tournament, with former world champions also making early exits.
Mark Selby was defeated 5-2 by Liu Hongyu in his opening match. Mark Allen suffered a 5-4 loss to David Lilley.
Wuhan Open champion Xiao Guodong was stunned by Duane Jones, losing 5-4 after leading 4-0.
Meanwhile, Masters champion Shaun Murphy has impressed, demolishing Thepchaiya Un-Nooh 5-0 with breaks of 83, 94, 94, 85 and 138.
"I was very very pleased with my performance today," Murphy said after his dominant display.
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Shaun Murphy is looking in good form
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With several top players already eliminated, the tournament has opened up significantly.
The absences of Ronnie O'Sullivan and Luca Brecel, who withdrew before the event, have further cleared the path.
Lower-ranked players now have rare opportunities to progress deep into the competition.
However, some formidable competitors remain in contention. Murphy in particular has looked impressive in Yushan.
His demolition of Un-Nooh suggests he could be the man to beat.
With the defending champion and world champion both gone, the World Open promises an unpredictable conclusion.
