Ulster Rugby have been rocked by two positive Covid-19 tests just days out from their second Pro14 fixture of the season.
Dan McFarland's side were forced to suspend all group training after two players tested positive for the virus.
It follows the latest round of PCR testing on Tuesday which returned a positive result for one senior and one academy player.
Ulster Rugby said the players are "currently asymptomatic" and are now self-isolating in-line with public health protocols.
Further PCR testing of players and staff is due to take place today, with Ulster scheduled to face the Ospreys at Liberty Stadium in Wales on Saturday.
"The Public Health Agency (PHA) has been informed, and its contact tracing process has started," Ulster said in a statement.
"Six close contacts have been identified through this process at this stage – five players and a member of the support staff.
"As a precautionary measure, all group training at senior and academy level has been suspended until further notice."
Ulster Rugby Medical Director, Michael Webb, added: “Following confirmation of two players testing positive, our priority continues to be the health and safety of our players and staff, so we have acted quickly with a number of measures, including standing down training from today, and asking those who have tested positive to self-isolate immediately.
“We will continue to work closely with the Public Health Agency and the IRFU to follow all of the necessary public health advice and assist with the contact tracing process as required, as well as provide support to the individuals involved.”
Further PCR testing of players and staff is due to take place on Thursday.
Ulster are scheduled to travel to Ospreys in the Guinness Pro14 this Saturday.
