Great Britain are still in contention for medals in three events going into Sunday's final day of the World Championships in Perth, Australia.
John Pink and Rick Peacock lost their overnight lead in the 49er class after struggling for much of the day, slipping back to third place overall.
In the 470 class, Hannah Mills and Saskia Clark picked up a race win to move up to the bronze medal position.
Nick Thompson and Paul Goodison remain in the shake-up in the Laser class.
Thompson, aiming for a third straight podium spot at the World Championship, is currently third in the standings with Olympic champion Goodison sixth after a 20th and an 11th on Saturday.
Two-time world champion Tom Slingsby of Australia holds a commanding 14-point lead but only 11 points separate second place from seventh ahead of the final medal race.
"There are certainly a lot of guys who are chasing my tail and I'm not too far away from second," said Thompson. "I think Sunday will be just about treating it as an open playing field.
"There's not much I can do other than try and do as best I can in the race. The points are all very close all the way through so I'll try and win the race."
In the 49er class, Pink and Peacock finished at the back of the fleet in two of the day's three races.
"It was a tough day and we didn't do as well as we could have hoped, but we're hanging in there - we're third now with the possibility of second so it's all still to play for," said 2009 world silver medallist Pink.
The British 49er crew for the Olympics has yet to be selected, but two other GB pairs lost ground on Saturday.
Dave Evans and Ed Powys will go into the elite 10-boat medal race in ninth place overall, while Dylan Fletcher and Alain Sign dropped from 15th to 17th. Britain's Beijing Olympians Stevie Morrison and Ben Rhodes were forced to withdraw from the event after Rhodes suffered a back injury.
Australia's home hopefuls Nathan Outteridge and Iain Jensen lead the class ahead of Denmark's Emil Toft Nielsen and Simon Toft Nielsen.
In the women's 470 class, Mills and Clark triumphed in the second race of their day, but there are three crews within four points of them, threatening their hold on third place.
"Looking back we're a bit gutted about that first race as we lost a few points which would've been nice to have going into tomorrow," admitted Clark.
Further back in seventh are another British crew, Penny Clark and Katrina Hughes.
Windsurfer Nick Dempsey picked up his best result of the week, finishing fourth in the last RS X race of the day, but 13th place overall, one ahead of fellow Briton Elliot Carney, was not enough to earn the 2009 world champion a place in Sunday's medal race.
Elsewhere, Brazilians Robert Scheidt and Bruno Prada clinched their second World Championship gold in the men's Star class. British Olympic champions Iain Percy and Andrew Simpson were also forced to pull out because of a back injury to two-time Olympic gold medallist Percy.