Following her first round win at last week's Japan Women's Open Tennis, Osaka entered the Premier-level event on a career-high ranking of No.69, making her Japan's No.2-ranked player. But across the net stood the Japanese No.1, who was looking to rebound from last week's opening round loss.
Osaka blasted seven aces in her stellar performance against Doi. Both players were evenly matched throughout the one and a half hour encounter, but it was Osaka who dominated the big points, bringing up five break chances and converting two - one early in each set.
For her part, Doi did her best to stay within touching distance of the 18-year-old, but couldn't find the weapons to put her under pressure. She brought up her first - and only - break opportunity late in the second set with Osaka serving for a 5-3 lead. Osaka batted it away with a zinging forehand down the line to stay on course.