US Open champion Coco Gauff cruised past fellow teen Brenda Fruhvirtova 6-3 6-0 at the Auckland Classic on Thursday, setting up a quarter-final against Varvara Gracheva in the Australian Open warm-up event.
Fruhvirtova, 16, matched Gauff in the early stages but once the American grabbed a 3-2 lead there was no looking back.
Gauff raced to 5-0 lead in the second set, and while the 19-year-old faced two break points serving for the match she saved both to win her first career meeting with the Czech.
"(Fruhvirtova) started off playing really well, and I was able to raise my level," Gauff said. "I thought I served well and did better on the returns, and I think I played a great match today."
At the Brisbane International, another tune-up event for the Melbourne Park Grand Slam, which runs from Jan. 14-28, former French Open champion Jelena Ostapenko beat Karolina Pliskova 6-2 4-6 6-3 to reach the quarters.
Latvian Ostapenko, who will meet former world number one Victoria Azarenka for a place in the last four, raced through the first set but looked frustrated as Pliskova fought back to claim the second.
"I get really mad when I miss some important points and I get really angry at myself," Ostapenko said.
"I'm a fighter and I really want to play kind of perfect. But I know nothing is always perfect. It’s just the way I am."
Two-time champion Azarenka beat France's Clara Burel 7-5 6-2, the 34-year-old Belarusian powering to a 4-1 lead in the opener before Burel drew level.
"I was trying to be aggressive, come to the net, but I felt like she was really on top of me," Azarenka said. "She did some amazing passing shots, some counter-attack balls."
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