Top seed Paula Badosa bundled out of Tokyo by Chinese teen Zheng

World number four Badosa, who was eliminated in the round of 64 at the recent US Open, struggled to gain a foothold against 36th-ranked Zheng and joined number two seed Caroline Garcia in making an early exit from the tournament. Badosa failed to hit a single ace and lost seven straight games before ending a miserable evening in the Japanese capital by swatting a return straight into the ground on match point.

The 19-year-old Zheng, who reached the last 32 at the US Open, said her win over Badosa was "not a surprise" for her. "I always know that I have the level," said Zheng.

"It's just when to make it. I'm so happy that I can make this match and I want to repeat it again." Zheng, who beat Japan's Misaki Doi 6-2, 6-4 in the first round, will now face either Belgium's Elise Mertens or Claire Liu of the United States in the quarter-finals.

Badosa had a bye into the second round.