UK Championship: Shaun Murphy knocked out by world number 124 Chen Feilong
|Betway UK Championship|
|Venue: York Barbican Dates: 27 November-9 December|
|Coverage: Watch live across BBC Two, BBC iPlayer, BBC Red Button, Connected TV, the BBC Sport website and mobile app from 1 December.|
Former champion Shaun Murphy and world number 12 Ryan Day were shock losers to first-year professionals on the second day of first-round action at the UK Championship.
Murphy, the 2008 winner, led Chen Feilong 3-1, but the Chinese player won five frames in a row to progress.
Welshman Day lost 6-2 to Joe O'Connor.
Three-time winner John Higgins, Masters champion Mark Allen and 2015 world champion Stuart Bingham all went through safely.
Scotland's Higgins survived a scare to earn a 6-5 win over the unpredictable Thai talent Dechawat Poomjaeng, while Northern Ireland's Allen was not at his best but comfortably beat Egypt's Basem Eltahhan 6-2.
But there was no safe passage for Murphy, whose defeat against world number 124 Chen provided the biggest upset of the tournament so far.
"I didn't see that coming. He played so well and deserved it," Murphy said.
"All was looking well at 3-1, but before I knew it I was staring defeat in the face.
"He potted some outrageous shots and I could do absolutely nothing about it. After the interval he was a different player; he played like a champion.
"It's been a terrible start to the season for me and it's a bit of a head-scratcher."
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Welshman Day, a two-time ranking event winner, was another surprise loser
Day, 38, struggled throughout a scrappy match which only produced three breaks of more than 50.
Leicester's O'Connor, 23, who only turned professional earlier this year, is making his third appearance at the UK Championship
He lost to former winners Neil Robertson and Selby on his two previous appearances, but showed no signs of nerves to close out victory.
"I am overwhelmed," he said. "I played well and it is definitely the biggest win of my career and I won't be forgetting it anytime soon."
Bingham & Fu ease through
Earlier Stuart Bingham and Marco Fu both romped into round two with 6-0 wins.
Bingham brushed aside former world number three James Wattana.
The 2015 world champion, twice a semi-finalist at the York Barbican, scored four half-centuries in the second half of the match.
"It was a bit of a slow start but I got going in the end," the 42-year-old said.
Hong Kong's Fu showed signs of a return to form after a tricky season following eye surgery earlier this year.
A break of 101 was the highlight of the Hong Kong player's whitewash of Hammad Miah.
In the evening matches, six-time world finalist Jimmy White had four half-century breaks, including a 93, but lost 6-3 to Thailand's Thepchaiya Un-Nooh, who rolled in a 110 in the penultimate frame.
Thursday's action at the York Barbican sees defending champion and six-time winner Ronnie O'Sullivan play amateur Luke Simmonds.
World number one Mark Selby also begins his tournament, against Blackpool's James Cahill.
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