David Boon, the match referee for the ongoing Ashes series in Australia, has tested positive for Covid-19 and will therefore miss the fourth Test, starting on January 5 at the SCG.
Boon will be replaced by Steve Bernard, who is part of the international panel of ICC referees and is based in New South Wales. He is expected to return to his role for the fifth Test, starting on January 14 in Hobart.
Boon, who turned 61 on December 29, is asymptomatic and fully vaccinated, including having had a booster shot.
He will remain in Melbourne, the venue of the third Test, and will quarantine for 10 days in line with Victorian state government health guidelines, which means he should be in the clear ahead of the fifth Test.
All players from both teams, their families, the England and Australian support staff and the match officials have been having daily PCR tests since Monday, December 27.
During the third Test, there were four Covid cases in England's touring party on the second day. Two members of the support staff and two family members of support staff returned positive Covid-19 rapid antigen tests. Play began 30 minutes late on the day, after all the players tested negative with rapid tests.
Earlier today, England coach Chris Silverwood was also ruled out of the fourth Test due to a family member becoming the seventh Covid-19 case within the touring party, and Silverwood thus forced to isolate for 10 days. Graham Thorpe will take on the head coach's role for England for the fourth Test.
Australia already have a series-sealing 3-0 lead, having won each of the first three Tests by handy margins. They secured the Ashes with an innings and 14 runs demolition of England at the MCG, having bowled the visiting side out for just 68 to win the Test inside three days.