Cook pushes away for one, giving Cummins another go at new man Malan.

Eek, the Middlesex batsman edges it into the ground and between keeper and slip as it races away to the fence.

Andrew Samson
BBC Test Match Special statistician

Joe Root has only converted five of his last 27 scores over 50 into a century.

Cook cuts but can't beat the man and just picks up one before Malan plays out the rest of Lyon's over.

Debate here over whether you have a problem with Joe Root playing that short or just the execution.

Perhaps better to shelve it on a slow pitch and with the man back. He also might have been beaten for pace a tad. But then again if he'd got on top of it and hit it down...etc, etc.

Let us know what you think.

Dawid Malan is the new man and defends it away to mid-on.

I dare say the words 'Joe Root' and 'conversion rate' are being combined in plenty of exasperated messages right now.

Jim Maxwell
BBC Test Match Special

Root fell for the trap. With two men back he couldn't resist playing the short ball.

Image source, PA

Can Lyon extract anything from this pitch and challenge Cook as he has in other Tests this series?

A touch of extra bounce here and there but Cook is able to rock back and punch away safely enough. A maiden to start for Lyon.

Ebony Rainford-Brent
Ex-England batter on BBC Test Match Special

It is all looking pretty good for England when you think they have got batting to come.

They will be feeling they are in a good position.

Cummins is up at 85mph but straying too straight and Root works it into the leg-side for one.

Steve Smith is currently off the field - we've heard he's suffering from a touch of illness too, but the skipper looks happy enough, sharing a joke with the sub fielders on the sidelines.

Cook picks up another single to deep-ish point.

Smith returns to the field and Lyon is about to enter the attack.

Stephan Shemilt
BBC Sport in Melbourne

The sun isn't as fierce as the previous two days, but the walk to the ground from the city was as sticky as a half-sucked boiled sweet, the type that makes you wish you had a spare shirt. There's a small amount of rain forecast and light clouds cover the stadium. Mercifully, there's a decent breeze inside, too.

England have seen off Hazlewood's first spell this morning.

Cummins is into the attack. How will his pace be? He was down a fair few mph yesterday, struggling with a stomach upset.

Lovely stuff from Root as he drives a wide-ish delivery from Bird out through the covers for three.

And that's even better from Cook - a vintage cut shot as he carves it away behind point to the fence.

Bird then over-pitches and Cook cover drives for a couple more.

Cook drives at a full ball from Hazlewood, it's momentarily in the air but safe enough and out through the covers for two.

The England opener defends a couple, leaves a couple and that's another Hazlewood over negotiated.

Graeme Swann
Ex-England spinner on BBC Test Match Special

Because of the nature of this wicket you have to pitch the ball up and it is almost like the batsmen are having throw downs because there are so many drives.

The ball sounds magnificent off Cookie's bat.

Bird continues, all very tidy but no real menace on this low and slow pitch.

Cook plays a few nice-looking drives off front and back foots but for no runs, until he flicks off his pads round the corner for a single.

A touch of reverse there, Bird throws his hands up but Cook was just about in control of it.

Nathan Lyon looks to be warming up.

Stephan Shemilt
BBC Sport in Melbourne

Queues at the ticket office. I've heard talk of 40,000 or so being here today.

So Root survives that appeal but can't add anything to score as Hazlewood completes a promising maiden. Perhaps a touch of reverse swing on offer there. England will be looking to just see Hazlewood out of the attack, he's been by far and away Australia's best bowler here.