New Zealand's Dan Slater is seventh in the fleet of the men's finn race at the Olympic sailing after the first two races.
Slater finished seventh in the first race and 11th in the second.
Sweden's Jonas Hogh-Christensen won both races and is in first place in the overall standings.
The next two races will be sailed on Monday.
In the men's star race, Hamish Pepper and Jim Turner finished 15th out of the 16 teams in the day's first race and 7th in the second.
Those results put them in 13th place overall with eight more races to go over the next week.
The women's Elliot 6m match race also got underway on Sunday with the 12 crews racing against each other in pairs in a round robin format.
The New Zealand crew of Jenna Hansen, Stephanie Hazard and Susannah Pyatt lost to the Netherlands in their first race and beat Sweden in their second.