Ding Junhui has withdrawn from this month's Tour Championship as a "safety precaution" and to "avoid extensive travel" from China.
The World Snooker Tour was working with the government to secure Ding an exemption from the 14-day quarantine policy for those arriving in the UK.
But the 33-year-old has decided not to travel, with his place in the eight-man event going to Scot Stephen Maguire.
The tournament starts on 20 June at Milton Keynes' Marshall Arena.
That is the same venue that hosted the Championship League event on 1 June, as snooker became the first sport to appear on free-to-air television in the UK during the coronavirus pandemic.
World number one and world champion Judd Trump, Neil Robertson, John Higgins and Mark Selby will be among the players vying for the £150,000 top prize.