PARIS, France - The top two seeded pairs in the Roland Garros doubles draw both needed to come from behind to survive the second round, with No.1 seeds Hsieh Su-Wei and Barbora Strycova saving a set point in the first set before pulling away 7-5, 6-1 over Marie Bouzkova and Arantxa Rus, and No.2 seeds Timea Babos and Kristina Mladenovic keeping their title defence alive with a 2-6, 6-4, 6-2 defeat of Kaitlyn Christian and Giuliana Olmos.
Hsieh and Strycova have lost just one match all year - to Babos and Mladenovic in the Australian Open final - and were fresh off their eighth title as a team in Rome, but were under pressure throughout a narrowly contested first set. Both Rus and Bouzkova saved break points in their first service games, with Rus particularly impressive in finding big serves and backhands in clutch moments - and once they had avoided the early deficit, the Czech-Dutch duo, who were playing together for the first time this week, grew in confidence.
Swinging away with relish and using Rus's power effectively, they scored the first break of the match on the Hsieh serve to go up 5-3, with Rus firing a searing return to seal it. But when it came to serving out the set, the 29-year-old faltered as the Wimbledon champions raised their level.
Efficient Hsieh volleying had saved the top seeds in the ninth game, where they had been two points from going down a set on three occasions, and the doubles World No.1 would also conjure up a fine dropshot to save set point as Rus attempted to close out the opening act behind her own delivery - and then an overhead to break back.
With this chance gone, the momentu shifted irrevocably. Bouzkova squandered a break point against Hsieh for 6-5 by sending a volley long, and the 22-year-old's groundstrokes went awry at the worst possible time as she conceded her serve for the first time while trying to stay in the set.
Hsieh and Strycova continued to pile the pressure on to gain a stranglehold of the match as the second set began, taking advantage of errant Rus forehands to capture the Dutchwoman's serve in the second game. From there, the WTA Finals runners-up rolled, showcasing their inimitable style as they casually and consistently put the ball beyond their opponents' reach. Both excelled at net, while Hsieh came up with one of the shots of the day as she reflexed an off forehand pass past Rus in the third game, and running off 12 of the last 15 points took them over the finishing line at speed, Hsieh wrapping up victory with her first ace of the day. Next up in the third round will be Istanbul champions and No.14 seeds Alexa Guarachi and Desirae Krawczyk.
Meanwhile, reunited for the first time since their abbreviated US Open campaign, Babos and Mladenovic faced a rematch with the pair they defeated in their sole match there, Kaitlyn Christian and Giuliana Olmos. In New York, the Franco-Hungarian duo had sailed through a 6-2, 6-2 win, but today faced a sterner test, falling behind a set before fighting back 2-6, 6-4, 6-2 in one hour and 44 minutes. Like Hsieh and Strycova, the defending champions' level rose as the match went on, and they would seal victory with a run of four straight games.
Elsewhere, No.4 seeds Barbora Krejcikova and Katerina Siniakova made it safely through to the third round as well, though the 2018 champions also needed to come from a set down before quelling Jennifer Brady and Caroline Doleide 2-6, 6-3, 6-4, while No.16 seeds Coco Gauff and Caty McNally squeezed past Kateryna Kozlova and Magda Linette 6-0, 3-6, 6-2.
However, the day ended with an upset as unseeded Americans Asia Muhammad and Jessica Pegula shocked 2019 US Open champions and No.3 seeds Elise Mertens and Aryna Sabalenka 3-6, 6-1, 6-4.