Judd Trump's defence of his World Grand Prix crown was ended as Tom Ford sealed a battling 4-3 victory in a nervy decider.
Trump jumped into an early two-frame advantage but struggled for fluency throughout the Round of 16 contest.
Ford registered the highest break of the week so far on his way to levelling proceedings, and forced a decider after Trump had moved back ahead.
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Both players traded regular, often basic errors as they battled for a place in the last eight, but the final frame eventually fell the way of Ford, who followed the scalp of John Higgins with a similarly impressive win.
"I went out there and basically gave him a 2-0 headstart - I was absolutely useless," Ford admitted to ITV.
"But all of a sudden I clicked into gear. It was a strange match. It was like a Jekyll and Hyde match."
Trump took the first frame in two visits, Ford unable to capitalise on an opportunity after Trump ran astray.
The 32-year-old added the second in similar fashion, his opponent going in-off when looking to force required snookers to seal a 2-0 Trump lead.
Ford would soon get on the board, though, designing the highest break of the tournament so far with a brilliant clearance of 133.
And the match was level a frame later as an unfortunate kick ended Trump's contribution, allowing Ford to pounce.
Both players had chances to move in front in a tense fifth frame, but it eventually went the way of the former world champion, playing a nice safety from behind the blue and then seizing on a red left by Ford to take a 3-2 lead.

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However Ford, a former semi-finalist at this event, hit back, taking Trump to a decider.
It was contested streakily, with both players missing seemingly simple colours while trying to build match-winning leads.
But it was to be Ford who eventually found his potting radar, firing in a brilliant red cleaning up after cleverly freeing the black from a tricky position by the cushion and rolling it, nervelessly, into the middle pocket.
"It felt a little nervy out there," said Ford. "I'm just glad to be through to the next round.
"It's going to be a tough match whoever I play."
The 38-year-old will face Mark Selby in the quarter-finals following the reigning world champion's 4-2 win over Mark Allen.
Across the dividing wall at the Coventry Building Society Arena, Yan Bingtao thrashed Martin Gould 4-0 in a scrappy match.
Gould had felled UK Championship winner Zhao Xintong in the first round of the World Grand Prix but could not reproduce his form against Zhao's compatriot.
Indeed Yan required only one break in excess of 50 to complete a victory without conceding a frame.
The Chinese starlet will play Neil Robertson for a place in the semi-finals.
The Australian completed a swift 4-1 victory over Anthony Hamilton, taking the second of three consecutive frames to start the match with a marvellous 108.
Hamilton grabbed a frame back but another telling contribution enabled Robertson to progress.
Mark Selby, the world number one, continued his tilt at another title when he defeated fellow Englishman Mark Allen 4-2 in a match that dragged on until almost 1am.
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