Australian 470 sailors Mat Belcher and Will Ryan need one more amazing race if they are to retain their world championship title.
They sit third in Buenos Aires, 16 points behind leaders Croatia.
The Croatian team were the last non-Australian crew to win a 470 world title, before Belcher went on his six-year run of wins.
"We are in medal contention and still have a small chance to win and it's never over until the end," Ryan said on Saturday AEDT.
The weed-filled course has made sailing difficult, but the pair posted an eighth and a second on Saturday to stay in third.
"Like everyone else, we're spending all our time clearing the weed to actually sail the race. But we're still in with a chance," Belcher said.
Belcher and Ryan have won the last three world titles together, and will need a strong performance in Sunday's double points medal race to win.
In the women's 470, Carrie Smith and Jaime Ryan finished the regatta in 18th overall.