John Higgins will miss the German Masters in Milton Keynes after testing positive for Covid-19.
Higgins, who reached the final of the Masters last week, was due to play Stuart Carrington in the first round on Wednesday afternoon.
Carrington will now receive a bye into the last 16 of the tournament while Higgins will undergo a period of self-isolation.
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A statement from World Snooker Tour said: “All other players involved in the remainder of the event have had negative results.
“Since WST events restarted last June, strict Covid-19 regulations have been and continue to be followed, under UK Government guidance.”
Judd Trump will start as favourite for the event after he missed the Masters due to a positive Covid-19 test of his own.
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The world No 1 says he feels even “hungrier” to succeed on his return to action.
“The first day or two was tough to watch," he told World Snooker Tour. "You just have to sit it out and wait to be allowed out from isolation. I knew I was in the German Masters, which was nice. It was something to look forward to.
"Hopefully that experience has made me even hungrier to go on and do things this week.
"I hope I can use it as a motivational thing. Going forward for the rest of the season, I hope to pick up where I left off in that great World Grand Prix final against Jack Lisowski before Christmas.”
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