Singapore, Oct 30 (IANS): Reigning Wimbledon champions Sania Mirza and Martina Hingis earned their third consecutive win to top the red group and enter the semifinals of the year-ending $7 million WTA Finals being played at the Singapore Indoor Stadium here on Friday.

Following their victories in the opening two round robin matches earlier this week, the Indo-Swiss tennis combine came up with another top-class performance to beat Hungarian-French fourth seeds Tímea Babos and Kristina Mladenovic 6-4, 7-5 in one and a half hours.

Playing on hard courts, Sania, who won the prestigious tournament last year with Zimbabwe's Cara Black, and Martina earned five breakpoint opportunities in the first set. They converted one which was enough to seal the set and take the lead in the contest.

Timea and Kristina came back stronger in the second set but the reigning US Open champions once again broke the fourth seeds to win the tie and comprehensively enter the semifinals.

The top seeded Sania and Martina, the only pair in the tournament to have not lost a set, will take on Chinese Taipei third seeds Chan Hao-ching and Chan Yung-jan in the last four round. The Chan sisters finished second in the white group.

The WTA Finals is an annual event played by the top-8 players/pairs of the year who are divided into two round robin groups -- red and white. The top-2 of each group progresses to the semifinals and the following winners to the finals.

The championship is generally considered the fifth most prestigious event on the women's tour after the four Grand Slam tournaments. It also has the largest prize money and ranking points after the Grand Slams.