No. 1 seed Donna Vekic of Croatia was one of several seeded players to fall on Tuesday at the Hamburg European Open, with Australia's Storm Hunter rallying for a 3-6, 6-3, 6-3 upset victory in the first round in Germany.
Vekic committed seven double faults and only saved five of 10 break points in allowing Hunter to advance.
Also in the first round, Eva Lys of Germany dismantled second-seeded Mayar Sherif of Egypt 6-1, 6-1, and Australian Daria Saville blanked Italian fourth seed Jasmine Paolini in the first set en route to a 6-0, 7-6 (3) win.
In a second-round match, Russia's Diana Shnaider toppled Austrian fifth seed Julia Grabher 6-4, 6-2. In the quarterfinals she will face third-seeded Bernarda Pera, an American who beat Estonia's Kaia Kanepi 7-6 (6), 6-1 for her second victory in as many days.
No. 7 seed Arantxa Rus of the Netherlands beat Russian teenager Maria Timofeeva 6-2, 4-6, 6-1 in a first-round match, and Italy's Martina Trevisan took down eighth seed Camila Osorio of Colombia 6-1, 6-3 in the second round.
BNP Paribas Warsaw Open
No. 1 seed and home-crowd favorite Iga Swiatek of Poland got past Nigina Abduraimova of Uzbekistan 6-4, 6-3 in the first round in Warsaw.
Swiatek saved six of eight break points and capitalized on her opponent's 10 double faults to earn the win.
No. 2 seed Karolina Muchova of the Czech Republic stormed past Belarusian Aliaksandra Sasnovich 4-6, 7-6 (0), 6-3, and No. 4 seed Lin Zhu beat Xiyu Wang 6-4, 6-2 in an all-China first-round match. But Czech third seed Katerina Siniakova did not join them in the next round, with Great Britain's Heather Watson scoring a 7-5, 6-2 upset.
Tereza Martincova of the Czech Republic upset fifth seed Shuai Zhang of China 7-6 (3), 6-4, and Lucrezia Stefanini of Italy beat Czech seventh seed Linda Fruhvirtova 6-1, 7-6 (4).
Other winners included No. 8 seed Linda Noskova of the Czech Republic, Yuliya Hatouka of Belarus, Tatjana Maria of Germany, Clara Tauson of Denmark, Jodie Burrage of Great Britain and Rebecca Sramkova of Slovakia.
Ladies Open Lausanne
No. 5 seed Emma Navarro, a 22-year-old American, handed France's Leolia Jeanjean a double bagel with a 6-0, 6-0 first-round win in Switzerland.
Navarro converted six of eight break-point opportunities and won 54 of the match's total 80 points to cruise to victory in just 53 minutes.
Second seed Elisabetta Cocciaretto had to rally past Switzerland's Celine Naef 3-6, 7-6 (1), 6-2, while ninth-seeded Diane Parry also used three sets to beat fellow Frenchwoman Fiona Ferro 7-5, 2-6, 6-2.
Danka Kovinic of Montenegro, Dalila Jakupovic of Slovenia, Sara Sorribes Tormo of Spain and France's Chloe Paquet and Clara Burel also won their matches. Two matches were suspended, with third seed Ana Bogdan of Romania tied one set apiece with Switzerland's Simona Waltert and fourth seed Lucia Bronzetti down a set to Tamara Zidansek of Slovenia.
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