Ronnie O’Sullivan and Judd Trump both face a battle to stay in the World Championship after falling behind in their quarter-final matches.
Five-time winner O’Sullivan trails Mark Williams 6-2, with defending champion Trump 10-6 down against Kyren Wilson.
In the final last-eight tie, Anthony McGill has established a commanding 7-1 lead over Norway’s Kurt Maflin.
Trump went into Monday evening’s session trailing 5-3 and searching for his best form.
And it proved to be a frustrating experience for the world number one, who twice reduced his deficit to a single frame but lost the chance to level the match by missing the final black in the 12th frame.
The trend continued as Wilson, who won his first ranking title at Trump’s expense in the 2015 Shanghai Masters, grew in confidence.
A superb break of 94 – the highest in the contest so far – and another of 80, helped the eighth seed construct a notable lead as he reeled off the last three frames.
Trump now faces an uphill task when the best-of-25 encounter against Wilson concludes on Tuesday afternoon.
No first-time snooker world champion has retained the title since the tournament moved to its current venue in 1977.
Source – BBC