U.S. Open champion Naomi Osaka suffered a 6-2, 6-4 straight-sets loss to world No. 27 Lesia Tsurenko on Saturday, failing to advance to the women's singles final at the Brisbane International.
The fifth-ranked Osaka had beaten the Ukrainian in their two previous meetings. A maiden Brisbane championship would have made Osaka the first Japanese man or woman to reach No. 3 in the world rankings.
"I just feel like I had the worst attitude today. I feel like I didn't really know how to cope with not playing well," said Osaka, who committed 26 unforced errors.
The Japanese second seed said she acted childishly when she made mistakes and admitted the psychological obstacle prevented her from winning.
"I feel like in a way that this experience for me is better than winning the tournament. I feel like today was a very valuable lesson," she said.
The 21-year-old Osaka was unable to earn a single break point in the 66-minute match at the Pat Rafter Arena. She wasted her first opportunity to break serve in the sixth game of the second set, allowing Tsurenko to move 4-2 ahead.
While Osaka showed visible frustration, Tsurenko converted her fourth match point to seal victory. She will play for her fifth career title in Sunday's final.