Third seed Flavia Pennetta won a tough encounter in the first round of the China Open in Beijing on Sunday.
The Italian needed three sets to get past China’s Han Xinyun 7-5, 4-6, 6-4 in a match lasting two hours and 27 minutes.
In other matches, American Sloane Stephens caused an upset when she beat ninth-seeded Karolina Pliskova of the Czech Republic 6-3, 6-2 and Ukraine’s Kateryna Bondarenko had little trouble getting past Barbora Strycova of the Czech Republic 6-3, 6-2.
Russia’s Anastasia Pavlyuchenkova got through against Julia Goerges of Germany, winning 6-2, 6-4, while Germany’s Mona Barthel beat Zhang Shuai of China 6-3, 6-2.
Alison Van Uytvanck of Belgium beat Slovakia’s Anna Karolina Schmiedlova 6-2, 6-4 and Spanish seventh seed Carla Suarez Navarro got past Lesia Tsurenko of Ukraine, who retired injured when behind 6-3, 0-0.
Monica Puig of Puerto Rico beat Zarina Diyas of Kazakhstan when she also retired injured with the score 6-4, 0-0. America's Irina Falconi won a close three setter against Daria Gavrilova of Russia 7-5, 2-6, 6-4.