Cook Islands swimmer Wesley Robert won gold in the 1500m freestyle event on the opening night of finals at the Oceania Championships in Fiji.
The 18 year old touched home in 15:42:27, almost 40 seconds clear of Hawaii's Michael Petrides.
Papua New Guinea, New Caledonia, Samoa and Fiji also claimed medal success at the Damodar Aquatic Centre in Suva.
PNG's Ryan Pini was second in the men's 50m butterfly event, while Samoa's Winter Heaven won the B final.
Compatriot Samuel Seghers won bronze in the men's 200m freestyle, a quarter of a second behind second place.
Samoa's Lushavel Stickland finished runner-up in the women's 100m backstroke, with New Caledonia's Anais Toven claiming bronze and Fiji's Adi Kinisimere Naivalu winning the B final.
And the Fiji team of Meli Malani, Matelita Buadromo, William Clark and Yolani Blake finished third in the mixed 200m freestyle relay.
Australia tops the gold medal count after day one of competition with six wins, while New Zealand won four events and Cook Islands one.