Aryna Sabalenka says she "guarantees" she will be better prepared next time she faces Serena Williams after losing in three sets at the Australian Open.
The powerful Sabalenka was among the favourites in Melbourne as she entered the tournament on the back of winning her third straight title at a WTA 500 event in Abu Dhabi.
She did not drop a set in her first three rounds before going down in three against 23-time Grand Slam champion Williams.
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The 22-year-old showed plenty of steel to fight back from 4-1 down in the decider to level the match, but her nerves finally gave way when she committed an array of errors while serving to stay in the match trailing 5-4.
"I felt like I missed my opportunity because I feel like if you are coming back from 1-4 and you're kind of feeling your game and you're there, you're fighting, you just have to take this opportunity," Sabalenka told reporters in Doha on Monday.
"I felt like mentally I was a little bit up and she was down. I would say it was not really smart mistakes from me. But it was good experience because I never played against these kind of champions like Serena.
"And going on the court, I was kind of like thinking what's going to happen, how she's playing, what's her power and all this stuff. Then I step in on the court and I understand, like, 'wow, actually I can play her, I can beat her'."
Sabalenka, who will defend her Qatar Open title this week, managed to match Williams' power from the baseline but felt her approach was not right.
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"I can guarantee that my mindset will be different going on the court," the world No 8 said. "I don't know what's going to happen on the court, but I know that my mindset will be much stronger than last time.
"Now I know what to expect from her and now I know where her level is. I think, yeah, it will be different next time."
Third seed Sabalenka has a tough opening match in Doha as she faces Garbine Muguruza.
Additional reporting by Reuters
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