Sabalenka's most potent weapon - her punishing serve - had become her biggest liability last year when she made a WTA-leading 428 double faults. At one point she even resorted to an underarm serve.
But she had no problem in Wednesday's quarter-final, committing zero double faults while winning 87% of her first serves to dispatch Gauff 6-4 6-0 in just over an hour.
"I feel a little bit different on the court this year. I feel like I'm a little bit a different player,
"Because before, I didn't have a slam, and every time I felt so much pressure from myself because I really wanted to get it. And every time something would happen, I would lose really close matches just because I really wanted it. I would miss so many easy shots," she said.
"Right now it's given me more belief and understanding what I have to do on those important matches."
The world number two from Belarus said January's Australian Open success has also allowed her to maintain a positive mindset in matches.
"I'm more calm on court, and I'm able to control my emotions, which help me to stay in the game no matter what," she said.
"Fight for every point, without losing my mind and without giving easy points to opponents."
Sabalenka will next face seventh-seeded Greek Maria Sakkari for a spot in the final of the WTA 1000 event in the Southern California desert.
