Travis Head's unbeaten century, with Steve Smith's 95 not out has given Australia complete control of the World Test Championship final against India at The Oval.
Put into bat after losing the toss on a green pitch, Australia lost Usman Khawaja for a duck and after lunch were reduced to 3-76 in cloudy conditions that made batting difficult.
However, after lunch the sun came out and Head (146) made batting look exceptionally easy, putting on 251 for the fourth wicket with Smith (95) to put the Aussies firmly on top.
"[After] Losing the toss this morning, we've done exceptionally well," Head told the host broadcaster after the day's play.
"There's still plenty there, as you could see with that second new ball. A lot of hard work to go tomorrow morning but nice to make a really good start.
"We want to play good positive cricket and put pressure on them tomorrow."
After a brief experiment as a makeshift opener in India, Head reprised his role as middle order dasher at The Oval, and instantly made his mark on the contest.
Head took the attack to India from the outset, scoring 28 runs from his first 20 balls with an array of flicks and clips off his pads, while Smith patiently compiled his runs at the other end.
Having opted to bowl first, Indian skipper Rohit Sharma would have been delighted to see the back of Khawaja in just the fourth over of the day, caught behind for 0 off Mohammed Siraj (1-67).
Further early wickets though were thwarted by the efforts of David Warner and Marnus Lauschagne, who weathered significant early pressure to see off the Duke ball, which swung from the outside and for the duration of the day's play.
Warner, who announced his hoped to retire after the SCG Test in January, looked back to his best early on, playing with a confidence and poise that had abandoned him during the last two years.
It was not the innings that instantly assures him of his place in the side until next January, but it was a hugely promising start, as the veteran opener rolled back the years with some exquisite footwork and stroke play — hitting 8 fours in his 60-ball innings.
Just as he was getting going though, Shardul Thakur (1-75) strangled him down the leg side, the Aussie opener gloving to Srikar Bharat for 43, who made an excellent catch to his right.
Labuschagne sent a ripple of fear through the camp when he was struck on the thumb by a vicious bouncer, but showed no ill effects and batted on after a brief stoppage.
He was, however, the next batter to fall, bowled for 26 by Mohammed Shami (1-77) by a beauty to leave Australia teetering at 3-76.
"We started quite well," Smith told ABC Sport.
"David Warner had good intent, looking nice and sharp. The opening partnership got things started in a difficult little period.
"Heady and I then just cashed in off the back of it."
And how.
Head signalled his intent right from the off, scoring the first of his 22 fours off his fifth ball and never looking back, reducing Smith to the role of sidekick.
"Travis just goes about his business, sees the ball and hits it," Smith told ABC Sport after the day's play.
"He shifted the momentum. It was a tremendous innings and I hope he has a few more runs in him tomorrow.
"I just played second fiddle at the other end and bided my time."
The century, Head's sixth in Test cricket, was his first overseas and the first ever in the World Test Championship Final.
Smith, who currently averages 121.50 with the bat at The Oval in Test matches, resumes on day two just five runs short of joining him.
Look back on how all the day one action unfolded in our live blog.
Key events
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Live updates
'Goodness knows what India are thinking': Jim Maxwell speaks...
Here's Jim Maxwell's thoughts on ABC Radio.
"Travis Head was just magnificent. He has been in a vein of form over the last two years that's been quite remarkable.
"Steve Smith was fairly dogged, perhaps more than we know he can be. He usually bats with a bit more freedom and intent.
"From an Australia viewpoint you could not ask for more.
"Goodness knows what India are thinking. To leave Ashwin out, even with a green tinge on the pitch.
"Did they really need four seamers?"
On the face of it, Jim, no they did not.
We'll wrap things up here in any case for the night/morning/whatever you call this unholy hour of the day.
Thanks for being with us, I'll be back for another day's action tomorrow from 7:00pm AEST.
Good morning.
Steve Smith hails 'really good day'
Smith has been talking to TMS and, by proxy, ABC Sport.
He started by paying tribute to David Warner.
"A really good day in the end. We started quite well. David Warner had good intent, looking nice and sharp. The opening partnership got things started in a difficult little period.
"Heady and I then just cashed in off the back of it.
"Travis played with good intent, put the pressure on. I just played second fiddle at the other end and bided my time."
He says Head was in sublime form.
"Travis just goes about his business, sees the ball and hits it. He shifted the momentum. It was a tremendous innings and hope he has a few more runs in him tomorrow."
He added that there is definitely enough in the pitch to take wickets.
"There is still enough in the pitch if you bowl in good areas.
"They were perhaps a bit short in that middle session, but Travis was putting pressure on them so it was a fine line."
Travis Head: 'A nice start'
Travis Head is speaking to the host broadcaster now.
He says he was pretty pleased with how the day has gone, but there is still plenty of work to be done.
"Obviously losing the toss this morning we have done an exceptionally good job on day one," he says.
"There is still plenty there. A lot of hard work to do in the morning but a nice start."
Head says it was nice having Steve Smith up the other end.
"I am making sure I am in really good positions. I felt like I was that for most of the innings [and] just trying to be adjustable on the job and work through and navigate through those periods and stay really relaxed at the same time, it's nice when you have a bloke at the other end playing as well as he is.
"I love playing with Steve. There are so many plans or unique thoughts that go into bowling to him because he is so unique.
"I know you said [he was] second fiddling [to me] but I feel like I am doing that to him.
"When he is in that form and moving the way he has and leading up to today, you can do and leading up to today, you can do a nice partnership and we're able to do that."
He says Australia needs to "double down" on their strong start tomorrow.
Key Event
Stumps: Australia 3-327 (Head 146, Smith 95)
Absolutely dominant.
Australia lost the toss and were put in to bat remember.
They lost Khawaja for a duck under leaden skies and everything looked a little bit sketchy.
However, Travis Head has taken the game by the scruff of the neck and put Australia in the box seat.
85th over - Mohammed Shami comes in again
Head pushes into the off side and takes off quickly — they'll run three. It's a lovely shot too from Head, standing up and pushing into the cover point region.
Steve Smith defends the first he faces.
This will likely be the last over of the day, so is Smith happy to be overnight on 91? Average check for Smith at The Oval: 120.50.
Smith shuffles across and leaves outside off.
FOUR! Smith drives through the covers for a boundary to end a dominant day one!
84th over - Siraj will have another
FOUR! Head just crushed that through the covers, a punched shot all the way along the grass and the hard new Duke flew to the rope.
FOUR MORE! Gorgeous shot, just leaning into a straight drive, the ball just cannoning off the bat. The timing is incredible, and he's made that look so easy.
Head scampers off strike after his double-boundary blow.
Steve Smith now, on 91 from 219 balls.
Smith looks at the ball as it goes down the leg side and although he doesn't pouch it, Bharat has done very well to stop that ball as it moved away from him.
Smith watches as the next flies past him outside off.
He leaves the last as well.
83rd over - Shami carries on
BEATEN! Head fends at that one outside off and is beaten, another ball just missing finding the edge.
Head tries to cut but misses at a close one. Head just needs to reign things in a little bit here.
Head defends into the off side, no run.
FOUR! Head just fended that one to backward point and the ball just kept on going and going and going until it hit the rope! Incredible timing and placement from Head.
Head pushes that one into a similar area but India have plugged that gap and it's just a single.
82nd over - Mohammed Siraj with the second new ball
Siraj sends that across Head's face, no run.
BEATEN! Head leaves the bat out there, dangling invitingly, but the ball just misses!
Head drives to extra cover but a really good stop by the fielder saves a couple of runs — it's just a single. Great effort in the infield.
Smith defends the first he faces.
He defends the next as well.
FOUR! And then drives the last through the covers for another boundary to move into the 90s.
81st over - Mohammed Shami comes into the attack
New ball is due, but India are not taking it.
Steve Smith defends the first couple.
Oh, hang on, now India take the new ball.
It will still be fresh-ish tomorrow, but the commentators are suggesting India should have just waited until tomorrow and you get their point, new day, new mindset, fresher legs, batters with minds that might have wandered...
Now Australia will come in tomorrow morning having already taken the initial shine off the new ball.
Smith defends solidly for the first couple of deliveries.
Wide outside off, Smith leaves it alone and it's a maiden.
80th over - Mohammed Siraj comes back into the attack
We should have stopped play by now, by the way, but we're playing the extra half hour because India are 11 overs short of bowling their allotted 90 overs. That's just woeful. If Australia got 6 penalty runs per over I bet India would have hurried up...
Anyway, Siraj is back and he'll bowl his 17th over.
One slip in place and Travis Head takes a single to bring up Australia's 300.
Smith defends a couple and then takes a single.
CLOSE! Head gets a bottom edge and the ball squirts through to Bharat — narrowly missing the stumps on its way through.
The forecast says, more cricket
As we close in on 300 with seven in hand at the end of day one, I'm thinking this will go well past three days
- Mike
And the crowd goes wild...
79th over - Jadeja comes in again
Jadeja brings out the Superman dive and can't quite get to a Travis Head push, and they run a single.
He fields Smith's flat-batted shot back down the pitch though.
Bowling again quickly, Jadeja watches the ball played wide of him to mid off for a single.
Head leans back and cuts, takes a single to deep mid wicket.
FOUR! Smith shuffles down the pitch and hammers the ball down the ground! Quite a flat shot, a couple of bounces over the boundary.
Smith defends the last.
It's a really beautiful day in London
78th over - Shardul carries on
There is a bit of swing out there, but not enough to trouble these set batters.
More swing, on the stumps, Smith motions that he's seen it to everyone watching and opens his mouth in faux astonishment.
Smith defends another, and then sees out the over.
77th over - Jadeja comes in again
Handy player to have up your sleeve when the over rate is bad, Jadeja. He fires through his overs.
Smith defends the first and then levers the second away for a single.
Head now gets an easy single to point.
Smith takes a single.
BEATEN! Head goes on one knee for the big heave and misses everything.
76th over - Shardul comes in again
Smith defends.
Now he hooks a decidedly non-venomous bouncer away for a single to square leg.
FOUR! Head goes over the top to deep cover and gets a one-bounce four. Lovely stroke and another hammer blow to the confidence of his Indian attack.
FOUR! An upper cut now! Casually leaning back and lifting it up over the skips and keeper.
BEATEN! How did that miss! Head missed it, the ball swung after pitching and moved just enough to miss the off stump! It's like there's a force field around Travis Head's off stump today! Strange shot though from Head, trying almost to cut a straight one.
He's tried to cut that too, but makes a mess of it and the ball flies through low to Bharat.
75th over - Jadeja spins through another set of six
Smith takes a single with a drive through the covers.
Head leans back and cuts to deep square leg for a single of his own.
Smith defends, and then he drives to cover, where the ball is fielded.
Smith drives again, powerfully, but gets no run there either.
This time he gets the ball wide of cover and takes a single.
74th over - Shardul carries on
Smith defends a couple, and then sees a clip to midwicket fielded well in that region by Rahane.
Smith clips again and the ball is fielded well, again, at midwicket.
A good yorker is dug out by Smith, who scampers through for a single to keep the strike.
Sorry, Steve
Hey Simon, could you keep it down a bit? I'm trying to concentrate out here - thanks
- Steve Smith
73rd over - Jadeja carries on
Smith defends the first and then gets an easy single off the second.
FOUR! Head goes off the back foot and powers that through the covers for four more!
That's the 200 partnership, off 295 balls
Head defends as Jadeja extracts from drift across from leg to off, just testing Head's technique.
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