The sixth seed, who reached the third round of the US Open earlier this month, survived a real scare in her Tokyo opener, finding her range in the knick of time to book her spot in the next round.
However, fifth seed Madison Brengle was not so fortunate, the American crashing out 6-1, 6-4 to Slovakia's Jana Cepelova to become the biggest casualty of the opening day's play.
Also checking out early was Ukraine's Kateryna Bondarenko, the eighth seed, who was bundled out by American Louisa Chirico in a 6-4, 7-5 defeat.
Chirico was joined in the second round by countrywomen Varvara Lepchenko, a 6-0, 6-2 winner over Japan's Risa Ozaki, and Christina McHale, who edged Ukraine's Kateryna Kozlova 6-4, 3-6, 7-6.
Currently in its sixth year, the Japan Women's Open serves as an appetiser for a quality field at the Pan Pacific Open later this month, which includes Spain's French Open champion Garbine Muguruza.