Roger Federer through to final after Hyeon Chung retires with injury
Chung unable to carry on because of blisters
Federer was leading 6-1 5-2 when Chung quit
Federer will go for 20th Grand Slam on Sunda
Swiss star will face Croatia's Marin Cilic
Federer 6-1 1-0 Chung
Federer only executed 32% of his first serves in that opening set, but he landed 14 winners compared to four from Chung.
He also send down four aces compared to one from Chung, who double-faulted twice.
Federer 6-1 1-0 Chung*
Barely a bead of sweat on the headband-bearing Swiss, who cracks down a second serve quicker than you can say '19-time Grand Slam winner...'
Back-to-back aces follow, and Chung punches a return long as Federer holds to love.
Mark Woodforde
Australian 12-time Grand Slam doubles champion on BBC Radio 5 live sports extra
He's used his experience and depth of his game. With the first serve not really operating in the first two games, he's been able to retool it and found some rhythm. It's one-way traffic.
*Federer 6-1 Chung
Roger Federer polished off that first set in 34 minutes, it felt like a majority of those were accumulated in that deciding service game.
Work to do for Hyeon Chung if he is to extend his dream Australian Open run.
Image source, AFPAustralian actor Eric Bana, aka the Hulk, and former Formula 1 driver Mark Webber are among the crowd today. Wonder who'd win if they had a couple of sets later?
Image source, Getty Images*Federer 6-1 Chung
Deary me.
Chung follows up an ace with an indefensible double to give Federer another shot at this first set.
And this time to Swiss converts.
Federer 5-1 Chung*
It's certainly resilient from Hyeon Chung.
He keeps clawing his way back to deuce, but Roger Federer is lethal on the forehand side and he whips in another untouchable winner.
Ace from the Korean to pull it back.
Deuce.
Federer 5-1 Chung*
Chung saves, again. But Federer picks him off with a superbly timed forehand winner, again.
I make that a third set point for the number two seed...
Federer 5-1 Chung*
Set point Federer, and this time Chung only has himself to blame.
He goes for the deftest of volleys, but drops it wide.
Image source, EPA#bbctennis
Kayleigh: All tennis should be played this early so I have something to keep me entertained at work tbh.
Dez Kamara: Chung is playing against Mr. Cucumber. Always cool and that is why he is Mr. Fed Express.
Federer 5-1 Chung*
Did Roger Federer just hit fresh air on his forehand side? Might need my glasses checking, but the Swiss just seemed to completely misjudge that...
There's nothing wrong with his forehand winner on the next point, coaxing Chung towards the net and then picking his spot down the line.
Back to deuce.
Federer 5-1 Chung*
Long.
Chung holds his breath and watches a Federer response drift narrowly beyond the whites of the baseline.
Deuce.
Federer 5-1 Chung*
Live text commentator's curse and all that, just as I praise Chung's serve he double faults.
Federer nonchalanty guides a backhand slice deep towards Chung's baseline and the Korean can't deal with it.
All of a sudden it's set point.
Image source, AFPFederer 5-1 Chung*
Federer's return has great depth and Chung can't pick it up from the baseline, before the Swiss flat bats a forehand long.
A slicing, jumping first serve from Chung forces the defending champion into the tramlines - 30-15.
Mark Woodforde
Australian 12-time Grand Slam doubles champion on BBC Radio 5 live sports extra
Chung is facing different shots that he has yet to see in the tournament.
People have tried to hit through him. Tennys Sandgren was not at the same level, and with Djokovic and Zverev they didn't play a tactically smart match.
Federer had a closed practice earlier and most of it was taking the pace off the ball and making it fall short.
Image source, AFPFederer 5-1 Chung*
A minor blip in the Roger Federer service game, that double fault.
He nails an ace to go 5-1 up in the first set.
Piers Newbery
BBC Sport at Melbourne Park
According to the local official weather centre, humidity levels are currently at 97%. Which is a bit sticky. Apparently Federer had a word with the umpire early on to get the aircon in Rod Laver Arena turned up, which is attention to detail for you.
Although asked after his quarter-final about his game plan for facing Chung, the Swiss said: "I don't know exactly how he returns and how he serves exactly. Those are two major aspects to the game.
"Those start the points. I have to figure that part out a little bit tonight or tomorrow."
He seems to be getting a handle on things...
*Federer 4-1 Chung
It might be stormy outside Rod Laver Arena, but inside it Roger Federer is the epitome of calm.
Bang, bang. He rattles to 30-0 without having to face a return, before double faulting.
He's human...
Image source, EPA#bbctennis
Andrew Neill: Lots of aces please Fed
He's 3-0 up so far!
*Federer 4-1 Chung
Hyeon Chung coaxes a forehand beyond the baseline.
Roger Federer takes a double break.