Root is, rather appropriately, on 66 at tea. With Jonny Bairstow unbeaten on 33.

Cue the warm embrace of a Joe Root half-century to steady England nerves.

Out strode Ben Stokes, who looked like he was trying to hit every ball out of the ground.

But after eight deliveries he feathered through to Alex Carey to leave England in trouble at 176-5.

Harry Brook ran out of luck though with one of the freakish dismissals you will ever see that dramatically halted England's momentum.

I know it is early, but this match has certainly lived up to the hype so far. That was another brilliant session.

Harry Brook was on the front foot straight after lunch - but then survived being dropped by Travis Head when on 24.

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

This is such a key partnership for England.

There was a real opportunity for Australia to open up the game after Stokes' wicket but Root and Bairstow have kept things calm despite still going at five an over.

They didn't let Australia settle.

It's well-balanced going into lunch but Australia will be pleased with five wickets on a pitch like this.

Simon Mann
BBC Test Match Special commentator

It has been a wonderful day. It has ebbed and flowed throughout.

England were set back by two quick wickets from Lyon and Hazlewood, but Bairstow and Root have steadied things.

There is still a lot of work to do because it is such a good pitch.

Jonny Bairstow takes his time doing some gardening in the middle of the wicket, just to make sure this is the final over of the session.

A single off the final ball means Bairstow will have the strike when the players resume and wraps up another thrilling session.

It is definitely Australia's, but Joe Root and Jonny Bairstow have launched something of a recovery.

Martin, Sussex

That's a big shout, Martin.

Here's Joe Root doing Joe Root things.

Daniel Cooper: Watching Bairstow and Root together at the crease is like going to your favourite restaurant and ordering your usual starter and main, just knowing how good it is however many times you order it.

Michael Sneddon: Cometh the hour cometh Sir Joseph Edward Root MBE.

owenwilkinson: How can people not love cricket!

A thick edge from Jonny Bairstow evades the outstretched dive of Cameron Green and flies away for four.

Flash, flash hard and all that.

We will probably have one more over before tea.

With you on that, James.

Here is one example:

James, Dorset

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

Joe Root just needs to bat his usual way, we've said it about Stokes too but the same is true of Bairstow.

You can have the flair around that, but most of England's batting line-up revolves around those three and how solid they are.

They can keep up with the run rate easily just by playing their normal game.

Simon Mann
BBC Test Match Special commentator

Three reverse sweeps, two have gone for four and one was almost out. Talk about confidence!

You just can't take your eyes off this.

Joe Root reverse-sweeps again the very next ball and this time it goes for four!

What confidence from the former skipper. That crowd absolutely loved that.

He did. A big glove from Joe Root and Australia lose a review.

Simon Mann
BBC Test Match Special commentator

He's reviewed it immediately. He must know he's hit it.

Roles reversed! Nathan Lyon succeeds in an lbw appeal but Joe Root reviews instantly, which usually means he has touched it.