MADRID (AP) -- Second-seeded Karolina Pliskova struggled to beat Lesia Tsurenko of Ukraine 7-6 (5), 2-6, 6-2 in the first round of the Madrid Open on Saturday.
Pliskova was up 5-2 in the first set but Tsurenko fought back to force a tiebreaker that Pliskova won by hitting two of her five aces.
Tsurenko recovered from a break down to claim the second set, but Pliskova broke her three times in the decisive third set.
"I'm not really happy with the way how I was playing," Pliskova said. "Definitely the best was the third set. I was playing more aggressive. Otherwise, I was losing all the long rallies. It was tough."
The Czech player has won titles this year at Doha and Brisbane, giving her eight for her career.
In a late match that didn't finish until after 2 a.m., Germany's Laura Siegemund came back from a 0-3 deficit in the final set to upset sixth-seeded Johanna Konta of Britain 3-6, 7-5, 6-4.
Also, Misaki Doi of Japan beat ninth-seeded Madison Keys of the U.S. 6-4, 4-6, 6-4, Eugenie Bouchard beat Alize Cornet 6-4, 4-6, 6-1, and Roberta Vinci saw off Daria Kasatkina 6-1, 1-6, 6-1.
Other first-round winners included Irina-Camelia Begu of Romania, Alison Riske of the U.S., and Kiki Bertens of the Netherlands.
On Sunday, top-seeded Angelique Kerber, defending champion Simona Halep, Maria Sharapova, and Garbine Muguruza all play first-round matches.