Seventh-seeded Marion Bartoli of France ended the unbeaten streak of women's world No. 1 Victoria Azarenka on Wednesday night with a 6-3, 6-3 victory at the Sony Ericsson Open in Miami.
It ended defending champion Azarenka's season-long win streak at 26 matches by posting her third win over a world number one and first in three years.
"I really went on court with a lot of belief in myself, and I stayed very focused at the end," said Bartoli. "I'm so happy."
Azarenka had five double faults and won just 49 percent of her first serve points as she tried to rally for the second straight match.
In her fourth round match, Azarenka dropped the first set and then fell behind 5-2 in the second set against Dominika Cibulkova before fighting back to win a three-setter.
But there would be no comeback this time as Bartoli used her counterpunching style to keep the world No. 1 off-balance.
Bartoli next faces Agnieszka Radwanska of Poland who beat Venus Williams in the previous round.