New Haven: Slovakia`s Magdalena Rybarikova sent top-seeded Simona Halep crashing out of the WTA Tour`s Connecticut Open in one of two second round upsets on Tuesday at the final US Open tune-up.
Halep, the reigning champ, had her serve broken six times and Rybarikova saved 10 of 14 break opportunities en route to a 6-2, 4-6, 6-3 victory at the Connecticut Tennis Center facility.
Second-seeded Petra Kvitova, last year`s runner-up to Halep, cruised past Ekaterina Makarova 6-2, 6-1 to reach the quarter-finals in a match that lasted just 48 minutes on the hardcourts.
Unseeded Alison Riske became the first player to reach the quarters by upsetting sixth-seeded Italian Flavia Pennetta, 6-1, 7-6 (7/3).
American Riske, who never trailed in the second set tie-breaker, blasted eight aces and was a perfect five for five on break points in the 94-minute match.
"There are a lot of top players here. I`m definitely proud to be the lone American left, and hopefully I can keep it rolling," she said.
"I knew that I had to attack her second serve because she places her first serve so well. I felt like I was going to get looks at it at any moment, so I just kind of stuck with it, and I ended up returning well today. I just played solid."
Riske jumped out to a 3-1 second set lead, but Pennetta was able to tie it at 3-3. The players held serve the rest of the way, setting the stage for the tie-breaker.
Riske snapped a four-match losing streak with a straight set victory over Casey Dellacqua in her tournament opener. Riske next faces Rybarikova.
In other second round action Tuesday, Czech Barbora Zahlavova Strycova eased past France`s Caroline Garcia in straight sets win of 7-5, 6-2.
Zahlavova Strycova had two aces, went four-for-five on break points and saved 12 of 13 on her own serve in the one-hour, four- minute match.