New Zealand's Jo Aleh and Olivia Powrie came out on top in a winner takes all battle between Hannah Mills and Saskia Clark (GBR).
Aleh and Powrie started level on 33 points with Mills and Clark and a battle between the two crews was in prospect.
However, New Zealand looked to have won the gold before the race was even half-finished when Great Britain trailed in ninth, two minutes and 29 seconds behind.
Mills and Clark did everything right at the pre-start and forced the Kiwis to the back of the fleet. But whilst the Brits went left the Kiwis went right and the Brits got caught in the pack and were unable to turn. Aleh and Powrie capitalised to take a commanding lead at the first mark and they further extended it through a light wind race to take the bullet by 41 seconds ahead of Giulia Conti and Giovanna Micol (ITA).
On winning the gold medal Powrie said, "It's not sunk in yet. We are overwhelmed. It's never finished until you finish and now it is time to celebrate."
"It might have looked easy, but there was a lot going on. We aimed to get clear and knew she [Mills] had to get out. We'd had a look at the course before the race and decided we were going for the right."
Although they had a great start the Brits could not get out of the pack and Clark said, "The thing I am most gutted about was that it wasn't a really good scrap for the gold. We got a really good start. They got out and we got wedged in."
Despite a penalty turn Lisa Westerhof and Lobke Berkhout (NED) managed to do enough to take bronze. "For us the medal race was really exciting as we were so close to the others - France and Germany," said Berkhout. "We had to do a penalty on the first downwind, but we fought back and we are proud of ourselves."
1. Jo Aleh and Olivia Powrie (NZL) - 35pts
2. Hannah Mills and Saskia Clark (GBR) - 51pts
3. Lisa Westerhof and Lobke Berkhout (NED) - 64pts
4. Camille Lecointre and Mathilde Geron (FRA) - 65pts
5. Giulia Conti and Giovanna Micol (ITA) - 73pts
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