Major League Rugby, the 12-team North American circuit that had started its third season, announced on Thursday that it will cancel the remainder of the 2020 campaign due to the coronavirus outbreak.
Health and safety guidelines from the US Centers for Disease Control and Prevention have banned large gatherings to combat the Covid-19 crisis.
A week after issuing a 30-day pause to the regular season, the rugby union league decided to shut down any attempt to restart the season and begin preparing for 2021.
"I am saddened to announce that the remainder of the 2020 season is cancelled," MLR commissioner George Killebrew said.
"We believe it is ultimately the correct decision as we factored in health and safety risks for all parties."
Killebrew vowed the league would return next year.
"I want to ensure our fans that there is no doubt MLR will be back in 2021 and will emerge bigger and better than ever before," he said.
"We will be using this time as an opportunity to grow all aspects of MLR and we're excited to continue this journey into 2021 and for many years to come."
The league grew from seven to nine teams from its 2018 debut to 2019 and added three more clubs in 2020 with Atlanta, Washington and New England joining.
When the season was halted, the San Diego Legion - which includes South Africans Dean Muir, Joe Pietersen and JP du Plessis - topped the table at 5-0 on 23 points followed by Toronto at 4-1 on 19 points and Old Glory DC at 4-1 with 17 points.
MLR also began adding more top names from overseas, notably prop Tendai "Beast" Mtawarira, who sparked South Africa to the 2019 Rugby World Cup title before joining Old Glory.