Serena Williams advanced to the Australian Open final, winning a semi-final shoot-out against Madison Keys on Thursday.

Top seed and five-time champion Williams won through 7-6 (7-5) 6-2 against maiden major semi-finalist Keys, who lacked no verve on the biggest stage of her blossoming career.

Williams booked a ticket to her sixth final at Melbourne Park, where she will meet Maria Sharapova in a rematch of the 2007 decider.

The first set was a serving exhibition - 37 of 78 points were unreturned serves, Williams responsible for 22 of them.

The second saw Williams break clear with two breaks of Keys' serve, although the 19-year-old made it tough for the 18-time major winner to finish the job - Williams needing nine match points.

Keys caused the first stir by breaking Williams and holding for a 2-0 lead but her first blink - a double fault, serving at 15-0 in the sixth game - saw the world number one swoop.

Keys followed her service blunder with another two unforced errors, and when she netted an attempted passing shot, Williams had levelled the set at 3-3.

A love hold saw Williams find her service groove - an ominous sign - but Keys bounced back from her previous wonky service game to make it 4-4, showing few signs of balking at the occasion.

At 5-5, Keys got aggressive on return - two blistering forehands helping her earn a 15-30 lead, and took a Williams service game to deuce for the first time in the match.

She did not extend on that pressure, with wild errors handing Williams a 6-5 buffer, but Keys had an easy hold to send the opener to a tie-break.

Williams pounced on a Keys second serve to take the first point against serve in the tie-break and lead 2-1, and the world number one reeled off four straight points on serve to move 6-3 up.

Keys saved two set points via aces but an unreturnable serve from Williams - a fitting end to a serve-dominated set - sealed the opener in 45 minutes.

The second got off to the worst possible start for Keys, broken to 30 after winning the first two points - giving her an uphill battle from the outset.

Keys' brave resistance was further quashed when she double faulted to hand Williams a 4-1 lead.

Staunch to the bitter end, Keys fought off no less than eight match points - but Williams inevitably advanced.