Aust sailors beat weed to sit third

Australian sailors Mat Belcher and Will Ryan have overcome a weed-riddled race course to sit third at the 470 world championships in Buenos Aires.

Despite their difficult battles with weeds, Belcher and Ryan sit third with two days of the competition remaining.

The Olympic gold medallists and defending world champions have recovered from a disastrous first day of competition in Argentina to now sit in a podium spot.

"To be honest, with the conditions for the first two races, they should not have been raced," Belcher said on Friday.

"There was too much weed on the course to fairly race, but we coped well."

At one stage there were 30 coaches' boats trying to cut up the weed on the course using their engines before a race.

Belcher and Ryan finished seventh, fourth, and sixth in three races on Friday (AEDT) to climb up the rankings.

New Zealand sit first, 11 points ahead of the Australians, with another day of racing before the double-points gold medal race.

In the women's 470, Carrie Smith and Jaime Ryan have moved up from 25th to 14th as they bid to secure selection for the Rio Olympics.

Racing will continue in Buenos Aires from early Saturday morning (AEDT).