Maria Sharapova was swept away in the first round of the Kremlin Cup in Moscow on Tuesday by Magdalena Rybarikova, while sixth-seeded Daria Gavrilova beat Kristyna Pliskova to make it to the round of 16.
Slovakian Rybarikova spoiled Sharapova's first appearance at the Kremlin Cup in a decade, winning 7-6(3) 6-4 in just under two hours to set up a second-round meeting with France's Alize Cornet.
Later on Tuesday Australia's Gavrilova beat Pliskova in three sets and will face Belarusian qualifier Vera Lapko in the second round.
Seventh-seeded Julia Goerges, of Germany, currently 27th in the WTA rankings, beat Russian qualifier Polina Monova in straight sets and will face Kazakhstan's Yulia Putintseva in the second round.
Twenty-year-old Russian Daria Kasatkina also upset compatriot Anastasia Pavlyuchenkova, seeded fifth, beating her 7-6, 6-1.
Kasatkina, who served up four aces in Tuesday's match, will face Katerina Siniakova, of the Czech Republic, in the second round.
Russia's Natalia Vikhlyantseva and Irina-Camelia Begu, of Romania, also move on to the second round after wins on Tuesday.
