Easy as that. A love service game sees Djokovic take the second set.

Those nine games took an hour so it was not one-sided but you fear Albert Ramos-Vinolas' chances came and went when he failed to take those four break points in the seventh game of the set.

That could be a very big moment in this match. Novak Djokovic fights off four break points in a 12-minute service game and holds to maintain his advantage in this second set.

Ramos-Vinolas responds with a few quick points and it's back over to Novak. He'll serve for the set next up.

He's still hobbling by the way.

Tomas Berdych is struggling to get over the line. A couple more match points come and go, this time on his own serve. Juan Martin del Potro breaks serve and from 5-0 it's now 5-2. A glimmer of hope for the Argentine?

Either Agnieszka Radwanska or Su-Wei Hsieh await Angelique Kerber in the next round.

Next on Rod Laver Arena, one Roger Federer...

Juan Martin del Potro has avoided the embarrassment of a bagel. The former US Open fights off a couple of match points against Tomas Berdych and at least gets a game on the board in this third set.

The end looks nigh though.

Angelique Kerber, speaking on court: "I knew before the match it would be tough. Maria is a champion so I was really trying to play my game. I am so happy we have 2018 and not 2017 any more.

"I learnt a lot from the last 24 months. I had a great 2016 and last year was a little bit tougher. Everybody who knows me knows I never give up. I had a really tough off season and was working hard to be here. It's just great."

Jill Craybas
Former world number 39 on BBC Radio 5 live sports extra

That was very impressive from Kerber. Sharapova knew how well Kerber was playing and felt the pressure of Kerber's movement and ball striking and just tried to press too much.

Angelique Kerber is the only Grand Slam champion remaining in the women's draw.

Based on that perforamnce, she has to be the favourite to add another title to her collection.

An angled shot from Maria Sarapova looks to be heading out, but a tiny bobble off the net cord falls the Russian's way!

First match point saved.

Ace out wide starts off Angelque Kerber's service game, before another attempted winner from Maria Sharapova drifts out of play.

Another almighty first serve from Kerber sends Sharapova sprawling and just like that, she has three match points.

Sharapova nets the forehand!

Angelique Kerber will serve for the match.

Ace from Maria Sharapova to start the game, followed up by a scrappy double fault.

Sharapova gets Kerber where she wants her before she goes for another drop shot - not sure on that tactic, but Sharapova nets the drop shot, and it's two break points to Kerber...

It was errors from Sharapova, rather than power from Kerber, that allowed her to hold her serve in that last game.

Here goes Sharapova with the serve...

A drop shot from Kerber and it's not great, with Sharapova racing to get to the ball, but her shot just lands over the tramlines.

Out again from Sharapova! Kerber, somehow, holds!

Wow.

An almighty yell of "come on!" from Sharapova as she thuds a furious winner cross court for break point.

She's overcooked that forehand, though! Deuce.

Excellent from Maria Sharapova.

She uses the full length of the court to hold to love.

Meanwhile, Juan Martin del Potro looks to be on his way out of the Australian Open.

He's been broken by Tomas Berdych in the third set.

Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra

It's mind over matter from Sharapova to try to sow some seeds of doubt into Kerber's mind. It's still a long road back but it wouldn't take too much to turn it around.

A challenge from Maria Sharapova, shaking her head as Hawk-Eye shows a uppish forehand from Kerber was out.

This isn't the best return game from Sharapova, though. She struggles with the angles on Kerber's serve, and the German holds with an emphatic yell.