British number three Naomi Broady was beaten in the quarter-finals of the ASB Classic by American Sloane Stephens.
Broady had two chances to win the first set but lost 7-6 (8-6) 6-3 in Auckland.
The world number 122 led 6-5 in the opener, but fifth seed Stephens held her serve to force a tie-break and saved a set point before taking it 8-6.
Broady, who won a controversial match to reach the last eight, broke to lead 2-1 in the next set, but Stephens won five of the next six games to progress.
"It was a tough one, Naomi's a great player," said Stephens. "She has had such a great week here."