Cook 244* - highest score v Australia
Smith drops Cook on 66 & 153
Cook & Broad (56) add 100 for 9th wkt
Root 61, Woakes 26, Bairstow 22
Lyon, Hazlewood & Cummins - 3 wkts
Australia lead 3-0 in five-Test series
Cook 131, Malan 13
Brief cry of "catch it" as Cook works Lyon away to short leg again. A leading edge follows and Lyon puts his hands on his head.
The final one is slung down leg and Tim Paine whips the bails off but Cook had gone nowhere. A maiden full of teasing deliveries from Lyon there.
Michael Vaughan
Ex-England captain on BBC Test Match Special
The thing that has been impressive with Cook in this innings is that he has hit in the 'V' with power.
Trail by 83
Aussie skipper Steve Smith - who is feeling unwell - appears to leave the ground again.
From sickness to rude health as Cook punches Mitchell Marsh straight down the ground for four. Lovely shot.
Cook swivels a short one into leg for one, before Malan leaves a couple to finish.
Michael Vaughan
Ex-England captain on BBC Test Match Special
England should be very disappointed if they don't bat most of today, if not the full day.
Australia have four right-arm seam bowlers all bowling around 84mph. Jackson Bird was down on pace. He looked lovely to face.
Lyon drifts too wide and Cook clips it away for a couple.
Yeesh. Cook gets a thin inside edge onto his pad and the ball loops up but crucially falls short of Cameron Bancroft at short leg.
Cook works it past Bancroft for a single.
#bbccricket
Mikey from Nottingham: Sat in the members end of MCG with my England top on. Aussie members trying to convince me that Lyon will take a five-for and they will be batting by tea at the latest. We will see...
Lyon is about to change his angle and come over the wicket to Cook. Will that improve the chances of this coming to pass?
Cook 123, Malan 13
Mitchell Marsh is on for his first spell of the day and is met with Alastair Cook tucking off his pads for a single, natch.
Dawid Malan happy to leave and defend the rest of the over.
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Low conversion rates are not important. Give me a batsman who has one of the highest averages in world cricket over someone with a high conversion rate and low to mid-40s average. Get off Root's back about a lack of hundreds and be grateful he's a run machine.
Paul
Trail by 92
Cook slices Lyon away to point for a single.
Malan looks determined to use his feet to the spinner. nudging it around but can't pick up a run.
Michael Vaughan
Ex-England captain on BBC Test Match Special
Australia are bowling a lot better than yesterday.
It is the kind of wicket that it is hard to get in on. You have got to play with patience. Joe Root had done until that poor stroke with the trap set.
It was a mental switch off. A lapse in concentration.
A rejuvenated Cummins continues and draws Malan into driving, it's a thick edge and runs away along the ground through a gap at gully to the fence.
That's better from Malan for the same result - using soft hands to guide it past the cordon this time and through to the boundary.
Cummins gets one through Malan's defences and onto the pads.
Big appeal from the quick, but umpire Ravi isn't interested. Looked to be sliding down.
Cook had set off and was halfway down the wicket. Malan sends him back and the opener makes his ground easily in time.
Stephan Shemilt
BBC Sport in Melbourne
That Root wicket is England's series in microcosm. A mistake in a strong position, the skipper not kicking on after doing the hard work. Root was disgusted with himself. A kick of the turf, head bowed, gloves thrown before he reached the boundary edge. The problem with throwing your kit is that you have to move it, which Root had to do as he stomped down the tunnel.
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I know the Ashes have gone but that shot from Root was Sunday league standard! Pathetic!
P Dawson, M Keynes
Cook tucks Lyon away into leg for single, with Malan doing the same as England pick up two from the over.
Ebony Rainford-Brent
Ex-England batter on BBC Test Match Special
England are still well set. Cook has done well this morning. It has been nice to see him using his feet nicely.
Joe Root will be frustrated with that wicket. He was looking set.
That's drinks. An even first hour after that Root dismissal, maybe even Australia edging it given how important that wicket could be.
Cook is still there though, unbeaten on 120.
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Jon Evans: I think Root needs to see a sports psychiatrist. You just know he is going to get to 60 and get out poorly. Got to be a mental issue.
Daniel: Root has had a nasty habit of cheaply giving away his wicket, make the bowlers work for it Joe. It's a hard enough game as it is without gifts with his talent.
Charlie Wetton: England. This is your job! If you did stupid things like Root has done there in any normal job, you'd be sacked. Dear me.
Ebony Rainford-Brent
Ex-England batter on BBC Test Match Special
Pat Cummins looks a different bowler today.
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