Melbourne, Jan 24 (IANS): Rising tennis star Madison Keys produced a coming of age performance to outplay and outgun No.4 seed Petra Kvitova in the third round of the Australian Open here Saturday.

Keys has been touted as one of the most talented prospects of women's tennis, and against Kvitova she certainly lived up to the hype, triumphing, 6-4, 7-5 in Rod Laver Arena to reach the fourth round of a Grand Slam for the first time. There she will face fellow American Madison Brengle, who defeated CoCo Vandeweghe, 6-3, 6-2.

"My hands are still shaking. I'm really glad I served that game out so well," Keys said after winning. "Right now, I can't even process anything - I'm just so excited to play Maddie in the next round."

It is not often that Kvitova plays second fiddle in the power department, but time and again she was forced onto the back foot by her 19-year-old opponent. This pressure gradually began to take its toll, the Czech producing an error-strewn game to hand over the decisive break at the end of the opening set.

The two had played once before, Kvitova emerging a comfortable winner in Tokyo a couple of years ago, but the American was a different proposition this time. At the start of the second game, Kvitova needed her best tennis just to stay in touch. However, with a tie-break beckoning, she finally wilted, missing a backhand to give Keys the chance to serve for the match.

With the finishing line now in sight, Keys didn't flinch, and if anything began to hit the ball even harder.