Unsurprisingly, it'll be Mitch Starc with the second over of the day. He goes full straight away and Root jabs his bat down. It's a touch wide from Starc, and he spears in a half volley that Root absolutely creams to the cover boundary. That's a delightful shot, and Root holds the pose for the photographers to get a load of. Starc saves a short ball for the final delivery of the over, and Root swivel pulls for one.

Graeme Swann
Ex-England spinner on BBC Radio 5 live

Anything over 250 for England will be challenging for Australia but they'll really be looking for 300.

They need to bat all day but they can't be as circumspect as they were in the first innings, especially against Nathan Lyon - hit him out of the park, get after him. They need to get Lyon on the defensive.

Image source, PA

Nothing more than 236 has ever been chased down at the Gabba. Worth bearing that in mind. The first run of the day comes as Mark Stoneman pats a ball down off his hip, before Root works an easy two through third man. A clip off the pads another another single to the total, before Stoneman ignores the rest of the over.

Mark Stoneman clonks his bat on the ground, Josh Hazlewood races in - and Stoneman ignores a good length delivery that zips through to Tim Paine.

Here we go. Steve Smith leads Australia out to the middle, before Joe Root and Mark Stoneman come skipping over the boundary rope. By the looks of things, it'll be Josh Hazlewood, who was superb last night, to open the bowling. He's already pawing furiously at the ground.

Jonathan Agnew
BBC cricket correspondent on Test Match Special

Cloudy and muggy at the Gabba. Possible light shower this morning. England need to bat all day...

Australia batsman David Warner, speaking to ABC: "The first session today will be key. It'll be dictated by how we bowl and then the way they bat."

On Starc hitting Root: "You don't like seeing people get hit in that way. At the end of the day this is the game that we play. You know the dangers of it. We asked him if he was okay, he said he was fine, and we got on with it."

Image source, PA

This is your ten minute warning. Stick the kettle on. Hoist the snacks out of the fridge.

Graeme Swann
Ex-England spinner on BBC Radio 5 live

I asked Jimmy and he said "there's nothing wrong, I'm knackered, I bowled 30 overs." He said they just went with someone else after lunch. It was exasperated, yesterday, by how badly Chris Woakes bowled. I think Joe was just going for a different option. I've had it from the horse's mouth that he's not injured.

Image source, Reuters

England batsman Dawid Malan, speaking to Test Match Special: "We're in a positive mood. Australia fought back well with Smith and Cummins and that dented us a little bit in terms of the way we were looking at the game.

"For us now it's about batting as long as we can and getting as many overs in the legs of these guys as we can. The longer we keep them out there, the easier it'll be to score."

On seeing Joe Root get struck: "When it happened I was looking at Chris Woakes - he's the nightwatchman so I was pretty keen to get him in there! It's never nice to see someone get hit. The wicket has obviously quickened up, which makes scoring easier, but it brings different challenges with it."

Image source, Getty Images

Graeme Swann
Ex-England spinner on BBC Radio 5 live

There's a giant crack opened up on the pitch by the off stump. It's in a horrible area. It's about ten foot long. The Australians will know that it will make the fourth innings tough.

This Test match has become the battle of the captains. Root has had the better time in the field, yesterday's afternoon period not withstanding, while Smith has dominated with the bat. Root has to do the same today.

Jonathan Agnew
BBC cricket correspondent on Test Match Special

England went to sleep in a position where they are effectively 7-2.

Yes, there is a chance that it could go wrong for them, but if they can battle to a lead of 230 or more, they will have a real chance of ending Australia's 29-year unbeaten record in Brisbane.

I say that with one caveat - that all of the England bowlers are fit.

Read more from Aggers here.

Phil Tufnell
Ex-England spinner on BBC Test Match Special

The key thing for me is that Nathan Lyon is turning it - that allows Australia to tie up one end and rotate their fast bowlers from the other.

Daniel Fenton: If Root goes in the first half hour then I'm off to bed to dream of an alternative ending to the Test.

BBC Radio 5 live sports extra

Test Match Special have slapped on the sun cream and are ready to bring you all the action from day four at the Gabba.

You can listen using the player at the top of the page, or by clicking here.

And if you've missed any of the action from this Test, or you want something to liven up your commute, you can catch up with the Test Match Special podcasts.

Imagine a line-up that would have had Joe Root and Steve Smith batting together...

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