British number one Johanna Konta has been knocked out of the Pan Pacific Open after a 7-5 7-6 (7-5) defeat by Czech Barbora Strycova.
The world number seven held a 3-0 lead in the first set before Strycova fought back to take the opener.
Konta, 26, wasted two set-point chances on the world number 25’s serve in the second set as the Czech held and then won the tie-break to seal victory.
“I’m very emotional and very happy that I won against Johanna,” said Strycova.
“I tried to focus on every point. She’s such a tough opponent to play, she doesn’t give you anything for free, you have to work for it.”
The 31-year-old will face Russian world number 23 Anastasia Pavlyuchenkova in the quarter-finals.
Konta was playing her first match since her shock opening-round defeat at the US Open.