Sofia Kenin has stunned home favourite Ashleigh Barty to reach her first grand slam final at the Australian Open.

Barty was looking to become the first Australian woman to make the final in Melbourne since Wendy Turnbull in 1980 and, as the top seed and world number one, expectations were sky high.

But 21-year-old American Kenin had other ideas and she took advantage of Barty's understandable edginess on a steaming hot Rod Laver Arena to win 7-6 (6) 7-5.

Barty had two set points in both sets but could not convert any of them and Kenin reeled off the final four games of the match.

The Russian-born Floridian could scarcely believe what she had achieved, and this victory will be enough to take her into the top 10 whatever happens on Saturday.

Barty, a reluctant celebrity, had spent the fortnight refusing to buy into the hype, but there was no doubt how much this meant to her.

The top seed could not pull away from Kenin, though, seeing three break points come and go at 3-2 and then a lead evaporate in the tie-break.

Barty had two set points at 6-4 but tightened up and her opponent took full advantage, winning the last four points.

Kenin's talent and competitive nature marked her out from an early age so it was no surprise to see her rise to the occasion on the biggest day of her tennis life.

As the temperature crept up, it was Barty who made the move in the second set with a break for 2-1, the baking fans on Rod Laver Arena willing her on.

Serving for the match at 5-4 she was poised to push the contest to a decider but again was unable to play freely and Kenin, whose speed of foot is matched by her speed of thought, continued to make life difficult.

The American saved two set points before retrieving the break and kept her foot on the accelerator to take her second match point.