Ronnie O'Sullivan crashed to a 4-1 defeat to Neil Robertson in the second round of the Ladbrokes World Grand Prix in Preston.
The Australian raced into a 2-0 lead following two half-century breaks of 80 and 70, with O'Sullivan rarely getting a chance to leave his seat.
The two cuemen were not at their fluent best in the next, with both players missing feasible shots, but Robertson came out on top to nudge into a 3-0 lead thanks to a score of 43 to finish the third frame.
Robertson, the world No. 7, put himself in a commanding position in the fourth to go 53-11 up but O'Sullivan fought back to need just the pink to take his first frame.
A poor positional shot from Robertson gave him a chance of the whitewash.
A tactical battle ensued with the remaining pink and black, O'Sullivan eventually prevailing to earn a lifeline, but that remained short-lived as Robertson rattled off an 83-break to reach the last eight.
World No. 4 Judd Trump fell at the second hurdle following a 4-1 defeat to Barry Hawkins, who will play Robertson for a place in the semifinals.
Hawkins opened the match by taking the first frame courtesy of a break of 64 and followed that up with a run of 86 in the next before Trump replied with the only century break of the match -- a clearance of 107 -- to reduce the scores to 2-1.
But the Ditton potter responded with another two half-century breaks of 73 and 72 to secure his place in the quarter-finals of a ranking event for a second successive time.
Liang Wenbo held his nerve to book his place in the quarter-finals following a final-frame 4-3 victory over Mark Allen.
Northern Ireland's Allen won the tactical tussle of the first frame, which took 31 minutes to complete, by potting the final black but Wenbo responded with a frame-winning break of 62 in the next to level the match.
The third saw both men miss good opportunities to take the upper hand before the Chinese world number 14's three-ball plant kickstarted a knock of 30 before adding a run of 27 to lead 2-1.
The 30-year-old Allen replied with a brilliant break of 95 to level the scores once again before Liang's equally impressive 85 left him one frame away from victory, but the Pistol ensured the match went into a decider courtesy of visits of 67 and 61.
But Wenbo came out on top in another tight frame to edge past Allen for back-to-back last eight appearances in ranking events.
The Masters 2017 runners-up Joe Perry also needed a deciding frame to overcome Martin Gould in a 4-3 win and earn his place in the last eight.
Gould, who knocked out world No. 1 Mark Selby in the first round, opened the match with a well-built 73 before grinding the next with a run of 39 to double his lead.
Perry hit back with a wonderful break of 85 to halve the deficit to 2-1 but took the next in a tightly-contested fourth frame to make it all-square.
Perry took the lead in the match for the first time with a break of 69 before the Pinner Potter forced a final-frame shootout with visits of 39 and 32.
Perry's safety game prevailed and he came out on top in the seventh frame.