A surfer tested positive for coronavirus and was stopped from boarding the World Surf League's chartered flight to Australia ahead of the Newcastle Cup next month.
American Caroline Marks was the only person to return a positive COVID-19 result among those booked on the Los Angeles to Sydney flight, which touched down at Mascot Airport on Monday.
Marks, 19, announced she had the virus in a video posted on her Instagram page on Sunday.
"I am following all the COVID-protocols and do [expect] to be competing once I am cleared," she said.
The World Surf League said in a statement that every passenger had been tested prior to travelling.
"All other tests were negative," it said.
"The necessary contact tracing has been conducted and Marks, as well as any close contacts, are self-quarantining and following all appropriate COVID protocols. WSL will continue to monitor the situation."
More than 100 surfers and officials arrived in Sydney on Monday and entered mandatory hotel quarantine for 14 days.
They will require a medical clearance from NSW Health before departing their hotels.
The Rip Curl Newcastle Cup, announced last month to replace the cancelled Bells Beach contest, is scheduled to start on April 1.
That leaves little more than a week before the Merewether contest begins for those exiting quarantine.
A coronavirus case among the large group of travellers from the United States is perhaps no surprise given an average 60,000 people tested positive each day across the country over the past week.
Marks is out of the Newcastle Cup and will likely miss the entire Australian leg of the Championship Tour, which includes an event at Narrabeen and two contests in Western Australia.
Three-time men's tour champion Mick Fanning wished Marks all the best.
"That sucks. Chin up. Get healthy and get over here! Wish you all the best," Fanning wrote on Marks' post.
Meanwhile, the WSL is expected to announce details of a ticket ballot for the Newcastle Cup in coming days.
The Merewether event will likely be screened off and limited to about 2700 spectators due to the state's social-distancing rules.
League officials have been in talks with ticket companies and working to come up with a fair system. WSL contests are not usually ticketed and difficulties arise because the competition is not held in set time periods.
It can vary between days and even stall for full days due to poor surf conditions.
The Newcastle Herald understands balloted general admission tickets will be free.
Screens are expected to be set up along Bathers Way and around the event precinct with the main spectator area to be on the sand.
