Kei Nishikori cruised to victory in his opening match in Acapulco on Monday, defeating Thiemo de Bakker 6-0, 6-3 in less than an hour.
The second-seeded Nishikori was sharp in his first match since capturing his fourth Memphis Open title a week ago, breaking his Dutch opponent six times and fending off the only break point he faced.
Also Monday, 35-year-old Victor Estrella Burgos of the Dominican Republic continued his strong form of late, beating Mexican wild card Lucas Gomez 6-4, 6-2. Estrella Burgos is coming off a defense of his title in Quito two weeks ago.
On the women's side, Britain's Johanna Konta, an Australian Open semifinalist, rallied to beat Estonia's Anett Kontaveit 6-3, 3-6, 6-4, and third-seeded Anastasia Pavlyuchenkova advanced when Urszula Radwanska retired while trailing 0-6, 3-2.
The top seeds in the men's and women's draws, David Ferrer and Victoria Azarenka, play their opening matches on Tuesday.