Ireland remained in the hunt to win the world rugby sevens series title after they came from behind to beat series leaders Argentina 21-5 in the quarterfinals in Singapore on Saturday.

The South Americans could have been crowned regular season champions with a win at the National Stadium and they took the lead when Tobias Wade opened the scoring late in the first half.

But Ireland hit back through Jordan Conroy just before half-time and tries after the interval by Terry Kennedy and Billy Davis secured their victory.

Ireland have not finished higher than third in this season's series and would need to win the Singapore event while hoping Argentina lose to South Africa in the fifth-place play-off in order to clinch the series title.

However, Conroy was delighted with his side's performance in the must-win game.

"This was a very important game. It was the decider for who could possibly win the whole series, so we were really focused and worked hard and we got the result," said the 30-year-old.

"If we had lost, we would have been out of the title race. But now we've put ourselves in a really good position for tomorrow and we will get our teeth sunk in then."

Ireland's semi-final opponents on Sunday will be Great Britain who trounced France 35-7 in their quarterfinal.

The British were beaten 19-5 by Ireland in their opening pool game in Singapore but battled back to beat Fiji and the United States to secure their place in the last eight.

The other semi-final will feature Australia and New Zealand who came through a pair of hard-fought quarterfinals.

Australia squandered a 19-point lead against South Africa but came back to win 29-24 in extra time while New Zealand prevailed 19-14 against the United States.

The regular season winners of the sevens series will be decided in Singapore with the top eight teams going through to the grand final in Madrid later this month while the bottom four sides will compete in a promotion-relegation event to determine the core teams for next season's series.

In the women's tournament, series co-leaders New Zealand and Australia remained on course for a showdown in Sunday's final after they maintained their perfect records in Singapore.

New Zealand topped their pool with emphatic wins against Ireland, Canada and Spain before seeing off Great Britain 24-5 in the quarter-finals while Australia beat Fiji, Great Britain and Brazil in pool play and sealed their place in the last four with a 24-14 win over Ireland.

Fiji will face New Zealand in the semi-finals after edging Japan 12-10 while France will take on the Australians following a 24-0 trouncing of Canada. (AFP)