The Australian's timing was perfect as he slipped out of the Croatian's cover and put a penalty on his rival. Read more
Brazilian hopes were boosted when Martine Grael and Kahana Kunze briefly hit the lead in the 49erFX.
Jake Lilley benefitted from the DSQ of a sailor who beat him in the final race, leap-frogging him into the medal race over a sailor who beat the bloke who was disqualified.
Leading after the first two races of the day, a 17th in the final race of the series makes a medal possible but the Gold unlikely.
The gap has blown out to 11 points with one more day of sailing before the medal race.
The British champion has a huge 24 point lead and the Silver also looks a foregone conclusion.
The womens division was close right to the end in the light conditions which favoured the good pumpers.
A second disqualification on their scorecard leaves them 20 points behind their British rivals with two or at most three more qualifying races left to sail.
A report was received last night of a gang of youths targeting Olympic tourists on Copacabana Beach and today a "suspicious package" was detonated outside the media centre.
The Australian has overcome a slow start to be in real medal contention with two qualifiers and the medal race left to sail.
Australian Ashley Stoddart has qualified for the medal race but is too far back to win a medal.
The Australian sits 10 points off the Gold and 10 points ahead of Bronze with the double-points medal race to be sailed on Monday Brazilian time.
Billy Besson and Marie Riou bounced back with three top results and are a serious threat to the leaders.
Local hopes are pinned on the daughter of their sailing legend Torben Grael.
The Australians admitted to poor decision-making which dropped them down to sixth, 23 points behind the Kiwis.