The second-seeded Nishikori was sharp in his first match since capturing his fourth Memphis Open title a week ago. He broke his Dutch opponent six times and fended 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 in beating Mexican wild card Lucas Gomez 6-4, 6-2. Estrella Burgos is coming off a defense of his title two weeks ago in Quito.
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.