Gallagher Premiership leaders Bristol’s game against London Irish at Ashton Gate on Saturday has been cancelled.
Irish returned positive Covid-19 tests this week.
Premiership Rugby said: “A significant number of their playing squad were ruled out of the match through the contact tracing process.
“This meant London Irish were unable to fulfil the fixture at Ashton Gate, something that was only confirmed this morning.”
Premiership Rugby added that Bristol have been awarded four match points following the cancellation, and Irish two, with the game recorded as a 0-0.
It means that Bristol finish top after the 22-game regular season and will host Harlequins in the play-offs at Ashton Gate next Saturday.
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The decision was made by a Premiership Rugby panel comprising chairman Andy Higginson and rugby director Phil Winstanley.
Exeter and Sale Sharks will meet in the other play-off tie, with Exeter needing a point from their regular season home game against Sale on Saturday to ensure that game takes place at Sandy Park.
It is the second match of the Premiership regular season’s final weekend to be scrapped for Covid-19 reasons, following the cancellation of Gloucester’s trip to Worcester, with Worcester awarded four points and Gloucester two by a Premiership Rugby panel.
Irish now have little chance of securing a top-eight finish and Heineken Champions Cup qualification next season.
A Premiership Rugby spokesperson said: “Our priority is the health and safety of everyone involved with London Irish and Bristol Bears, and we will give the clubs any support they need. We wish everyone affected a full and speedy recovery.
“Neither Premiership Rugby nor the club will be naming any of the players or staff involved, and we would ask everyone to respect their privacy.”
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