Geoff Burke-USA TODAY Sports

No. 1 seed Emma Raducanu advanced to the second round of the Zavarovalnica Sava Portoroz when her first-round opponent, Dayana Yastremska of Ukraine, retired Monday night in Portoroz, Slovenia.

Raducanu was already two points away from winning the match at the time. She led 6-2, 5-3, 30-0, having saved three of four break points while converting four of her five opportunities to break Yastremska's serve.

No. 2 seed Beatriz Haddad Maia of Brazil opened with a 7-6 (3), 6-3 win over Clara Tauson of Denmark. Haddad Maia served up four aces and converted five of eight break points.

No. 5 seed Ekaterina Alexandrova of Russia beat Ukraine's Marta Kostyuk 7-6 (5), 5-7, 7-5, despite committing 14 double faults. And No. 9 seed Anastasia Potapova, also from Russia, needed almost two hours for a straight-sets win over Claire Liu of the U.S., 6-4, 7-6 (5).

Chennai Open

Wild card Karman Thandi rallied to beat No. 8 seed Chloe Paquet of France 4-6, 6-4, 6-3 for an upset victory in her native India.

Thandi, ranked No. 359 in the world, saved five of eight break points. She came back from down 3-2 in the second set, winning four of the last five games in the set to extend the match.

No. 5 seed Rebecca Peterson of Sweden beat Victoria Jimenez Kasintseva of Andorra 6-2, 7-6 (4). Sixth seed Qiang Wang of China outlasted Belgium's Yanina Wickmayer 6-4, 1-6, 6-4, and Canadian seventh seed Rebecca Marino handled Russia's Anna Blinkova 7-5, 6-2.

Other first-round winners included the Czech Republic's Linda Fruhvirtova, Poland's Katarzyna Kawa, Canada's Eugenie Bouchard and Japan's Nao Hibino.

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