Daniela Hantuchova beat Yanina Wickmayer 6-2, 4-6, 6-0 in the first round of the Bank of the West Classic on Tuesday.
The 46th-ranked Hantuchova, once ranked as high as No. 5, played to the full three sets for the 269th time since 2000.
Wickmayer, ranked No. 56, reached the semifinals of last year's Classic.
In other matches, sixth-seeded American Varvana Lepchenko beat qualifier Michelle Larcher de Brito of Portugal 6-2, 6-4; qualifier Coco Vandeweghe, a finalist last year, downed Romania's Monica Niculescu 6-0, 6-3; and Russian qualifier Vera Dushevina topped New Zealand's Marina Erakovic 6-2, 6-1.
Second-seeded Samantha Stosur is scheduled to play a later match against Olga Govortsova, followed by No. 7 seed Ursula Radwanska against Christina McHale.