Second seed Caroline Wozniacki held firm to edge Simona Halep in a classic Australian Open final on Saturday, claiming a long-awaited grand slam title after two heart-breaking near-misses.

In a captivating tussle played out in stifling humidity that saw the temperature go above 30C, the Dane hung tough in a nerve-shredding final set to win 7-6(2) 3-6 6-4 under the lights at a heaving Rod Laver Arena.

The victory means the 27-year-old will replace Halep as number one in the world rankings on Monday.

Twice a runner-up at the US Open, Wozniacki also becomes the first Dane to win a Grand Slam singles title.

Halep, too, had been hoping to end the wait for a first major title to add to her number one ranking, but she has now lost in the Australian Open final as well as two French Opens.