Ana Ivanovic made a comfortable start to her Monterrey Open title defence on Tuesday, on what was a good day for the seeds in Mexico.
The Serbian top seed overcame Czech qualifier Nicole Vaidisova 6-1 7-6 (7-4) at the WTA International event.
Ivanovic broke serve six times during the 72 minutes on court as she was tested by the former world number seven.
Vaidisova retired in 2010 before making her comeback late last year, with this performance her best since returning.
It was a busy day at the event after Monday was rained out.
Italian second seed Sara Errani was on court for just over an hour, thrashing American Lauren Davis 6-0 6-3.
Caroline Garcia, the third seed, was pushed before claiming a 7-5 7-6 (7-5) victory over Italian Karin Knapp.
Timea Bacsinszky – champion in Acapulco last week following a win over Garcia in the final – overcame 10 double faults to edge Yanina Wickmayer 7-6 (10-8) 3-6 6-4.
Anastasia Pavlyuchenkova overcame a slow start to get past Anna Schmiedlova 4-6 6-3 6-0.
Jovana Jaksic's serve troubled her as 14 double faults proved costly in a 6-3 3-6 7-5 loss to Slovakian eighth seed Magdalena Rybarikova.
The only seed to fall was Alison Riske, the American going down to Vera Zvonareva 6-4 6-0.
Kristina Mladenovic was too good for Tereza Smitkova in a 6-4 6-4 victory and Francesca Schiavone battled past Bethanie Mattek-Sands 3-6 7-6 (7-3) 6-4.
In other matches, Pauline Parmentier beat Aleksandra Krunic 3-6 6-4 6-1 and Polona Hercog brushed past Ana Sofia Sanchez 6-2 6-3.
Qualifier Urszula Radwanska was a 7-6 (7-0) 7-6 (7-3) winner against Maria-Teresa Torro-Flor and Lesia Tsurenko crushed Shelby Rogers 6-2 6-0 in 51 minutes.
Johanna Larson beat Kiki Bertens 6-3 6-2 and Timea Babos claimed a 6-4 6-3 win over Silvia Soler-Espinosa, while the final match of the day - which finished in the early hours of Wednesday - saw Daniela Hantuchova beat Monica Puig 7-6 (7-1) 3-6 7-5.