Roger Federer is hitting these balls back so low to John Millman, plenty of slice, and Millman is so unlucky that his backhand from out wide ends up in the net.

Deuce.

Good, deep hitting from John Millman, wrong-footing Roger Federer on the baseline, and Federer just about gets away with a volley that Millman thwacks into the post.

Down comes a Federer ace for 30-15 but another error on the forehand takes us to parity.

Now then! Down the line aims Federer, misses, and it's break point to Millman.

So, just to recap: Serena Williams and Naomi Osaka have been knocked out, 15-year-old Coco Gauff is through to the fourth round, Caroline Wozniacki played her last ever match and Stefanos Tsitsipas, champion at the year end ATP Finals, is two sets down to Milos Raonic.

A nice quiet day in Melbourne so far...

That's a winner and a half from Roger Federer, the ball nestling right in the corner of the court, but John Millman serves into his body to race to a 30-15 lead.

The longest rally of the match so far goes Millman's way, the Australian defending so well before Federer floats a poor drop shot into the net, and Millman wallops an ace to hold.

An off-balance Millman hits a forehand into the net from the baseline to hurry Roger Federer along to a 30-0 lead.

Federer misses a cross-court push but as Millman pushes a volley return long, the Swiss holds to 15.

Here's what Federer said about John Millman prior to this match.

"I think the next match is really going to be a test for me because John is going to be there. He's fit like a fiddle," Federer said.

"He's from this country, so naturally also it's going to be different intensity. I think this is going to be a good test for me."

First job done for John Millman - he holds to love as Roger Federer makes a mess of a volley.

It'll be hometown here John Millman to serve first.

Right, Roger Federer will have to go some way to beat that excitement!

He's taking on John Millman, who stunned him at the US Open in 2018.

Right, we're going to take a quick five-minute tea break to recover from that, and we'll be back very shortly for Roger Federer's match against John Millman.

My word.

What a star.

Image source, Getty Images

More from Gauff on her schoolwork: "I'll probably do homework tomorrow because I want to go to sleep tonight.

"My teachers are giving me some time because considering the circumstances... they're letting me submit some assignments late, so that's nice!"

Asked if she wants to know who her opponent will be next: "I mean sure, why not. I don't really care who I'm playing at this point!"

"I'll probably be asleep because they play late."

American Coco Gauff, speaking on court: "I don't know where that came from. Honestly, like, what is my life? two years ago I lost first round in juniors and now I'm here!

"I was telling myself one point at a time and keep fighting. You never know what happens on this court.

"I love it down here, oh my gosh! Thank you guys from the bottom of my heart. I'm on the Rod Laver Arena! I can't believe it!

"I've walked past Rod Laver a couple of times in the hallway but I've never met him- if he sees this, tell him we can set up a meeting sometime. I need a selfie for Instagram!"

Coco Gauff is close to tears as she speaks on court.

A gutted Naomi Osaka gives Coco Gauff a huge hug at the net before waving to the crowd as she exits.

She was just never on it today. A brief fightback early in the second set but her backhand, in particular, let her down.

Blooming heck, and again!

Three forehand errors in a row from Naomi Osaka, who slumps to her haunches, looking utterly disconsolate.

Three match points to Coco Gauff!!

And again!

30-0.

Long goes Naomi Osaka's return of serve.

15-0.

Here. We. Go.