Naomi Osaka booked a spot in the third round of the Charleston Open on Wednesday by beating Germany's Laura Siegemund in straight sets.
Tenth seed Osaka defeated the world No. 74 Siegemund 6-3, 7-6 (10-8) at the Family Circle Tennis Center.
Osaka played aggressive tennis and served six aces against one of last year's semifinalists. She saved four set points in the second set, while hitting 31 winners throughout the match to Siegemund's 25 to seal the win in just over 2 hours.
"I guess (I'm happy with) just winning," Osaka said. "I was kind of upset throughout the whole match, to be honest, so I was very glad that I was able to win today."
The 20-year-old won her maiden WTA title at last month's BNP Paribas Open in Indian Wells, but said she does not feel the pressure or expectations building up.
"I'm not really paying attention to anything. I'm super tired all of the time and I feel like everything has gone by really quickly," Osaka said. "I'm just really trying to focus on my matches here and I'll think about the other stuff later."
Awaiting Osaka in the third round is fifth seed Julia Goerges of Germany, who advanced after beating American Kristie Ahn in three sets.