The British and Irish Lions have been hit by a Covid-19 case in their camp in South Africa.
One unnamed member of the management tested positive in a round of testing carried out on Wednesday.
He and four other people – two players and two staff – are isolating and the rest of the squad are being re-tested.
If further positive tests emerge, the Lions may be forced to cancel or postpone their scheduled tour match against the Sharks.
Even if the rest of the party is given the all-clear, the game will start at the later time of 7pm UK.
Saturday’s tour match against the Bulls has already been postponed after a Covid outbreak in the South African side.
It comes amid growing fears for the Test series, which is due to begin on 24 July, after more Springboks tested positive for Covid.
“We have followed all necessary precautions since the start of the Tour, which included regular testing and rigorous COVID-19 counter measure planning and protocols,” said Ben Calveley, managing director for the Lions.
“Our priority is to ensure the health and safety of the entire touring party, which is why we quickly isolated the players and staff upon receiving the news of the positive result.
“Everyone has subsequently been lateral flow and PCR tested. The Medical Advisory Group await the results of the PCR testing in order to make a decision on tonight’s game.
“The five individuals effected will be monitored closely during isolation and receive the best possible medical attention as we await the results of their PCR tests.”