Charleston - Venus Williams dropped out of the Volvo Car Open on Thursday, losing to Yulia Putintseva of Kazakstan 7-6 (5), 2-6, 6-4.
Williams, seeded third and ranked 14th, had a chance to gain a place in the top 10 with a victory in the match. Instead, Putintseva won the final two games of the final set to beat Williams for the first time in four tries.
Williams became the fifth of the top eight seeds in Charleston to lose before the quarterfinals. Top-seeded Angelique Kerber avoided that earlier in the day with a 6-2, 6-3 victory over Slovakia's Kristina Kucova.
Kerber is the defending champion after winning the title in last year's Family Circle Cup. The second-ranked German star was not her best, but good enough to put away Kucova. Kerber broke her opponent seven times, including the final game.
Williams seemed set to join Kerber in the quarter-finals after the seven-time Grand Slam winner ran off the last four games of the second set and led 2-1 in the third. But the 21-year-old Putintseva dug in to pull off the upset.
Putintseva fought through five deuces - three of them with Williams a point away from going up 3-1 - to tie the third set and then run out to a 4-2 lead.
After Williams rallied back a final time and the large, stadium court crowd cheering her on, Putintseva bore down to close out the victory and beat a second former Volvo champion in as many matches.
Putintseva defeated 2009 winner Sabine Lisicki on Wednesday before her win over Williams, the 2004 champion here.
Putintseva jumped around after the victory, pumping her fists and celebrating. Ranked 61st in the world, she entered the match with a 3-14 record all-time against players in the top 20.
Williams' steady serve unraveled down the stretch: She made seven of her 11 double faults in the third set.
Williams, who was seeking her second WTA title this season and 50th overall, said the bounces did not go her way.
"Sometimes, it just comes down to luck," she said. "And there's no easy matches, and I tried to continue to play aggressive, but (it) just wasn't in the cards today."
Kerber continued to gain confidence in the season's first clay-court tournament. She needed a third-set tiebreaker to win her opening match on Tuesday night. This time, Kerber relied on her steady groundstrokes and relentless returns to knock off Kucova.
Kerber broke her opponents' serve seven times and said she began to the feel the excitement here she did a year ago when she captured the title.
"I think the feeling is coming back like I had last year because right now, I'm feeling much better on clay again," she said.
No 5 seed Sara Errani of Italy and No 7 Sloane Stephens of the United States go for quarterfinal spots later Thursday.
Others advancing into the final eight were No 14 seed Daria Kasatkina of Russia, a 6-0, 6-4 winner over American wild-card entrant Louisa Chirico; Russia's Elena Vesnina, who topped Lourdes Dominguez Lino of Spain 6-1, 6-3; and Laura Siegemund of Germany, who beat Croatia's Mirjana Lucic-Baroni 7-5, 6-2.