Madison Keys believes letting go of the internal pressure to win a grand slam title was the key behind her breakout Australian Open triumph.

Keys stunned world number one and two-time defending champion Aryna Sabalenka at Rod Laver Arena in Saturday's final, securing a 6-3 2-6 7-5 win.

The 29-year-old, who previously lost to Sloane Stephens in the 2017 US Open final, became the oldest American (male or female) to win their first major singles title in the Open Era.

On her 11th main-draw appearance at the Melbourne Park event, she also equalled Caroline Wozniacki for the most entries required by a female player to win their maiden title.

Speaking in her post-match press conference, an emotional Keys revealed she had worked to get to a place where a grand slam victory was a bonus, rather than a requirement.

"I think everything happens for a reason. I think for me specifically, I had to go through some tough things," she said.

"It forced me to look at myself in the mirror a little bit and try to work on the internal pressure that I was putting on myself.

"From a pretty young age, I felt like if I never won a grand slam, then I wouldn't have lived up to what people thought I should have been. That was a pretty heavy burden to carry.

"I finally got to the point where I was proud of myself and proud of my career, with or without a grand slam. I got to the point where I was okay if it didn't happen.

"I didn't need it to feel like I had a good career or so I deserved to be talked about as a great tennis player.

"I feel like finally letting go of that internal talk that I had just gave me the ability to actually go out and play some really good tennis to actually win a grand slam."

Asked what she had done to get to that place, Keys responded: "Lots of therapy.

"I really bought into it. In the past I had always tried to go the sports therapy route, where it was more about routine and controlling things you can control and all of that.

"I was always good enough at that, but to really start digging into how I felt about myself and really being honest with myself about it... it was really hard because I didn't really want to be the person that felt like I was struggling.

"Just being really honest and actually getting help and actually talking to someone, and not just about tennis but about how I felt about myself... it was very uncomfortable.

"I never really like to be uncomfortable, but I honestly think that had I not done that, I wouldn't be sitting here."