Top seeds Sania Mirza and her Taiwanese partner Yung-Jan Chan sailed into the quarterfinals of the $200,000 Istanbul Cup with an easy 6-3, 6-1 win over the Romanian pair of Sorana Cirstea and Agnes Szatmari in Turkey on Tuesday.
Sania and Yung-Jan will take on the Greco-German duo of Anna Polunina and Stella Menna in the last eight stage of the Tier III WTA Tour event.
The top seeds overcame a patchy start to storm past their unseeded rivals for a comfortable victory.
Sania and Yung-Jan were broken twice in the first set but more than made up for that with four breaks of their own in the opening set.
The Indo-Taiwanese combination put up an even better display in the next set and held their serve besides breaking the Romanians twice to clinch the match.
Earlier, Sania bowed out of the singles competition in the first round itself, losing to American Meghann Saughnessy.
The Indian ace, who is coming back after a 2-1/2 month-long injury layoff, was seeded eighth in the singles draw.