Fiji secured a thrilling 24-17 victory over New Zealand to win the final of the Glasgow Sevens as they claimed their fourth title this season in the penultimate event.
Reigning World Series champions New Zealand, the 2014 winners in Glasgow, had ensured their qualification for the Rio Olympics next summer after winning their quarter-final against Scotland earlier on Sunday.
The All Blacks led 12-5 at the interval in the final, before Fiji turned things around to leapfrog South Africa in the standings.
Fiji now lead by five points with a total of 147 ahead of the final event in London.
"We are in a good spot," said Fiji head coach Ben Ryan. "We have put ourselves in a terrific position now to win our first series in 10 years. Third place would win it next week, but we want to win back-to-back titles. And London wouldn't be a bad place to win the title."
New Zealand sit on 139 points and coach Sir Gordon Tietjens believes they can still retain their crown.
""We are in with a chance. Anything can happen," he said. "It will be really tough, and we are looking forward to London now. We are pleased to qualify for the Olympics but let's see what happens next weekend in terms of the world series."
Sevens will make its debut at the Olympics next year, with South Africa and Fiji ensuring their qualification on Saturday.
England, on 117 points and 16 clear of Australia, are in the driving seat for the fourth and final berth, having ended the weekend in third after a 24-19 victory over the United States, following their 5-0 semi-final defeat to New Zealand.
Fiji beat the US 19-5 after a 15-0 win over South Africa in the last eight.