American Coco Vandeweghe ousted second- seeded Frenchwoman Marion Bartoli in the first round of the $235,000 Monterrey Open on Tuesday.
Vandeweghe broke the former champ's serve eight times and ripped 11 aces to come away with a 4-6, 6-3, 6-1 victory on the hardcourts at Sierra Madre Tennis Club. Bartoli captured this event in 2009.
The other top players cruised in their matches.
German Angelique Kerber played like the top seed as she disposed of American Samantha Crawford, 6-3, 6-3.
Third-seeded Russian Maria Kirilenko defeated Mexico's Ximena Hermoso, 7-5, 6-1, and fourth-seeded Serbian Ana Ivanovic bageled Russian Marta Sirotkina 6-0, 6-0 in a scant 45 minutes.
Fifth-seeded Anastasia Pavlyuchenkova, who won this title in 2010 and 2011, was trailing fellow Russian Nina Bratchikova, 4-2, in the first set on Monday when play was suspended for rain. Pavlyuchenkova recovered quite nicely, winning all 10 games played on Tuesday en route to a 6-4, 6-0 victory.
Eighth-seeded Ayumi Morita of Japan also leveled Slovak Jana Cepelova 6-0, 6-1.
Additional opening-round wins came for American Lauren Davis, Russian qualifier Alla Kudryavtseva, Serbian qualifier Jovana Jaksic and Croats Donna Vekic and qualifier Tereza Mrdeza.
This week's Monterrey champ will collect $40,000.