Tsitsipas looks irked as he whacks a forehand long and then Federer comes racing forward, rushing Tsitsipas behind the baseline.

Bam. Body serve from Federer for 40-0, and a ripper down the line hands him a swift hold.

* denotes next server

Much better from Stefanos Tsitsipas, serving into Roger Federer's forehand, and the Swiss reels off consecutive errors.

Tsitsipas cracks an ace down for 40-0 but then he just misses a pass at an approaching Federer to get his opponent on the board.

And that's a more comfortable hold for Tsitsipas as Federer nets a backhand.

BBC Radio 5 live sports extra

So close to the court they'll feel like ducking when Federer nails a serve.

The BBC commentary team have a great spot on Rod Laver Arena.

Tsitsipas wrong-foots Federer with a swipe down the line, but a big first serve into the body hands Federer a 30-15 lead.

Good serving from Federer, skipping forward and slashing a follow-up winner into the corner, and the Swiss ups the pace to ensure a hold.

Russell Fuller
BBC tennis correspondent at Melbourne Park

There was enough entertainment in that opening game to write an 800-word report.

This match could get very tasty indeed.

Time violations, a grumble at the umpire and some gorgeous stroke play.

And that's just the first game.

Shot!

Cross-court goes Stefanos Tsitsipas with a big forehand.

And this time, the Greek holds as an angled whip from Federer drifts long!

Just the eight minutes for that first game...

Image source, Reuters

Big first serve from Tsitsipas, and Federer nets.

Tsitsipas is within a point of holding - oh, but an insane rally at the net, both players stretched left and right, ends as Federer spins over a backhand that Tsitsipas can't return.

Tsitsipas whizzes down a first serve that's called out - he challenges, and its in!

Tsitsipas saves break point. Federer isn't happy, and has a word with the umpire.

40-40.

And Stefanos Tsitsipas misses his serve!

That's a double fault and it's break point to Roger Federer.

Oh, Stefanos Tsitsipas has been given another time violation!

That means he's lost his first serve, so Roger Federer will get a look at a second serve...

Image source, Getty Images

Roger Federer tries to pass Stefanos Tsitsipas at the net, and floats his forehand just long.

Advantage, Tsitsipas - but the Greek makes a horrible mess of a high backhand volley to take us back to 40-40.

And into the net goes the Roger Federer backhand!

Deuce.

Hello, Tsitsipas has been given a warning for a time violation...

Roger Federer comes running up to the net, and Stefanos Tsitsipas slams a backhand at his feet that the Swiss can't return.

Federer is on the board at 30-0 with a backhand winner, and he makes a better move forward this time to pop a winner in front of a stretched Tsitsipas.

Now then. Tsitsipas overworks a forehand and Federer, from 30-0 down, has a break point...

Image source, Reuters

Ready?

Play.

Stefanos Tsitsipas will serve first.

Stefanos Tsitsipas has modelled his one-handed backhand on Roger Federer after watching videos of the Swiss on Youtube.

It'll be interesting to see how they match up today...

Stefanos Tsitsipas on life on tour: "I think I'm comfortable meeting new people and having a discussion with someone," he said when asked about his perceived shyness.

"Not many of the players want to be friends on the tour. That's a problem.

"That's an issue unless you speak the same language. That makes sense.

"But I would love to have more friends on tour."

Read more about the Greek here.

We're going to need to talk about Stefanos Tsitsipas' Twitter game at some point.

And Roger Federer?

Well, we know all about him.

He's going for his seventh Australian Open title, his 100th career title and Grand Slam title number 21.