Katie Boulter was unable to follow up her brilliant opening round victory against world No 17 Linda Noskova as she bowed out of the Japan Open to the experienced Sorana Cirstea.
Boulter's victory against Czech Noskova was her first win against a top-20 opponent since beating Paula Badosa at Wimbledon in July.
But the Brit ran into inspired Cirstea, losing 6-3 6-1 in 68 minutes, with the 35-year-old Romanian sealing her spot in the quarter-finals with a near-perfect performance.
"I'm very happy to be in the quarter-finals and I thought I played a very solid match," said Cirstea. "I'm happy with the performance and hopefully I can keep going."
Boulter, who reached a career-high ranking of 23 in 2024, came into the tournament having suffered five opening-round defeats from seven tournamen