There are two days left in the fourth and final test of the series.
Khawaja 137, Smith 67, Starc 34 and Broad 5-101
England 13: Hameed 2.
The England trail is over 400 runs.
The scorecard is a summary of what happened.
On the second day of the fourth Test in Sydney, Khawaja scored a century to put Australia on top.
Khawaja, playing his first Test in a year, made 137 as Australia declared at 416-8.
The 35-year-old left-handed pitcher received good support from Steve Smith and Mitchell Starc, who both made 34.
Stuart Broad claimed a fine 5-101, including bowling Khawaja late in the day, but Australia held on to make England face a tricky 20 minutes with the bat.
England closed on 13-0 after Zak Crawley was caught in the slips off a Starc no-ball.
England's problems were familiar, with Joe Root dropping Khawaja on 28 off Jack Leach, who struggled for rhythm.
Ben Stokes did not bowl for the rest of the day despite returning to the field after pulling up with a side injury.
England are facing a tough task on a pitch that has begun to show variable bounce and a batting line-up that is yet to pass 300 in the series.
Khawaja makes a recall count.
Khawaja scored 37 on his debut against the same opposition at the same ground, but he made a century at the same venue.
After being dropped in England, Khawaja was dropped in his first Test for two years, but his strong early season form for Queensland put him in contention for a recall.
He adjusted quickly on the second day after a few early plays and misses, but he was able to get 28 when Root put down a chance to slip.
Khawaja cut and drove the bowler as he struggled to control the pace.
He was not flashy, but he did a series of singles to grind England down and move towards three figures.
He was given a standing ovation by the crowd and his young family as he reached his ninth Test century, with Khawaja imitating basketball great LeBron James' Silencer celebration to the delight of the fans.
The only question left for the selectors is if Khawaja keeps his place when Head returns for the final Test, almost every change Australia have made has worked.
On a day-to-day basis, England labour is on up and down.
The bowlers were able to trouble the batters before fatigue and errors crept in, but it was a mixed day for England.
Broad, who said before the Test that he had been frustrated watching on from the sidelines, found pace and bounce to unsettle Smith.
Smith seemed set for a century on his home ground but lost his concentration after being struck on the hand by a delivery from Broad and fell to the ball behind.
Broad sent a thick edge toRoot at first slip, before a vicious short ball ended Pat Cummins' stay.
Alex Carey slogged the ball up into the air and was well held by Jonny Bairstow, while Wood was bowling consistently at 90mph and beat the bat on numerous occasions.
The concerns over Leach that crept in after his difficulties at the Gabba remain. The spinner struggled for consistency and Australia was able to disrupt him further by working easy singles.
He was unlucky not to dismiss Khawaja, but he still lacks the control that England look for in a spinner.
England had some moments where they were on top, but Australia was resilient. They buckled down in those moments, content to play out maidens and tire the bowlers out, something England have yet to do with the bat.
They said 'Australia's day, no doubt about it'.
Being selected for Australia is a bonus for me. I am enjoying my life. I didn't think I was bad at 35.
I've been in a good spot since I got dropped. I don't have anything to prove to anyone. I enjoy playing cricket at my local club. I'm enjoying the game.
"It was Australia's day, no doubt about it," said Stuart Broad. I thought Khawaja played well. We didn't grab hold of him, but he gave us one chance.
We are still in the game and tomorrow is important. It is a good opportunity for a batting group that hasn't stamped their authority on this trip to do it, because day three is a really important day in Test cricket.
Steven Finn was a former England bowler and he said that England had an opportunity to bowl Australia out for 300 and then take a first-innings lead.
"You can sense the frustration England had with Australia being six down to get a good score on the board."
