The Super Rugby season was in serious doubt Saturday after New Zealand ordered everyone entering the country to self-isolate for 14 days in a bid to slow the spread of coronavirus.
It effectively rules out overseas teams playing games there for the foreseeable future, and should New Zealand sides leave for overseas clashes they would have to go into quarantine on their return.
"SANZAAR is now reviewing the full impact on the Super Rugby tournament," the governing body said, adding that its executive committee would hold an urgent meeting to decide what to do.
New Zealand Prime Minister Jacinda Ardern said the self-quarantine order would be reviewed after 16 days. It applies to all inbound travellers except those from Pacific Island nations.
The tournament is seven rounds into its 18-round regular season.
The Canterbury Crusaders were playing Japan's Sunwolves in Brisbane on Saturday and will be able to return home to New Zealand before the midnight Sunday deadline.
But the Highlanders were in Buenos Aires preparing for their clash with the Jaguares, which is set to be played behind closed doors in line with an edict from city authorities.
They are due to host South Africa's Golden Lions next weekend in Dunedin, but that would appear impossible if they have to self-isolate on their return.
Also next weekend, the Auckland Blues are scheduled to play Australia's ACT Brumbies at home, with the Waikato Chiefs in Durban to play the Coastal Sharks.
The tournament was already facing headwinds with fans barred not only from games in Argentina but also Australia from next weekend.
New Zealand so far only has six confirmed cases of the virus and has recorded no fatalities.