Naomi Osaka has lamented having a poor attitude her upset semifinal loss to world No.27 Lesia Tsurenko at the Brisbane International.
The US Open champion was dominated by the unseeded Ukranian, making 26 unforced errors to lose 6-2 6-4 in 66 minutes at Pat Rafter Arena on Saturday.
"If I'm being really frank, I just feel like I had like the worst attitude today," Osaka said.
The Japanese second seed was off her game from the start, broken in the first game and again at 4-2 despite fighting back from 15-40.
Osaka, ranked fifth in the world, sunk further when she doubled-faulted to hand Tsurenko the advantage at the beginning of the second.
Tsurenko brought up two match points at 5-3, but was held off when her 21-year-old opponent hit three aces and a drop-shot winner to hold.
Any hopes of Osaka repeating her quarter-final performance when she fought back from a set down against eighth-seeded Latvian Anastasija Sevastova were snuffed out in the next game.
Osaka had a chance to fight her way back into the match with the second set at 3-2, showing visible frustration when she failed to take advantage of two break points.
"I feel like I didn't really know how to cope with not playing well," she said.
"I was sulking a little bit and like there are moments that I tried not to do that.
"But then the ball wouldn't go in and then I would go back to being like childish and stuff.
"So I think like that was sort of my main problem today."
While the performance may not boost her confidence ahead of the Australian Open in just over a week, Osaka was seeing it as far from a sign of vulnerability.
"I feel like in a way that this experience for me is better than winning the tournament," she said.
"This helpless feeling I have, I think today I learned sort of what I have to do to not fix it, but what I can do to like improve the situation.
"I feel like today was a very valuable lesson."
Tsurenko ultimately blasted 20 winners to go one better than her semi-final appearance in Brisbane in 2013.
She will face former champion Karolina Pliskova or 34th ranked Donna Vekic in the final on Sunday as she bids for a fifth WTA title.