|The 2021 Betfred Masters|
|Dates: 10-17 January Venue: Marshall Arena, Milton Keynes|
|Coverage: Watch live on BBC TV, BBC iPlayer, BBC Red Button, BBC Sport website and the BBC Sport app. Highlights on BBC Two and online.|
World number one Judd Trump and Jack Lisowski have tested positive for coronavirus and will miss the Masters.
Both players were tested on Friday as part of strict protocols surrounding the event, which starts on Sunday.
Trump, who was due to play David Gilbert in his opening match in Milton Keynes, has been replaced by Joe Perry.
World number 14 Lisowski's place has been taken by Gary Wilson, who will face Kyren Wilson.
Perry and Gary Wilson were present in the tournament 'bubble' as substitutes and have returned negative tests.
The event, which is being held behind closed doors, has been moved from Alexandra Palace to Milton Keynes to follow Covid-19 regulations.
World Snooker Tour confirmed the positive tests in a statement, adding: "WST is following extensive Covid-19 guidelines in a 'bubble' environment for this event.
"All players are tested two days in advance of their first match, and after the test they remain in isolation until the result is received.
"All other players and officials tested at the event so far have had negative results.
"Trump and Lisowski will now undergo a further period of self isolation and will receive the support of WST and WPBSA."
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