On another chastening and sweltering day at the SCG, England’s bowlers toiled without significant reward as Australia raced past their 346 first innings total to close on 479-4 leading by 133.
Khawaja’s 171 provided the bulk before he became Mason Crane’s first Test wicket, but it was the partnership of 104 in just 158 balls between the two brothers from Perth which really sunk England.
Shaun Marsh will return in the morning two short of the second century of this series while younger brother Mitch walked in unbeaten on 63.
Both could do serious damage to England’s position on day four.
Moeen Ali struck to remove Smith holding a chance low in his follow through when the Aussie skipper mistimed a straight drive – a rare highlight on a bruising tour for the all-rounder.
The only other wicket to fall, Khawaja, went to Crane, who was a rare positive from an otherwise dispiriting day for the tourists.
Khawaja had batted in his usual languorous style but there was no doubting the quality of his innings.
Yet he might have fallen earlier on 132 to Crane when the bowler and his captain Joe Root reviewed a lbw shout given not out when the batsman offered no stroke.
They were right to review with the ball going on to hit the stumps but Crane was to have any celebrations cut short when the big screen showed he had overstepped.
Having a first Test wicket chalked off for over-stepping is becoming a peculiarly English problem with Mark Wood, Ben Stokes, Tom Curran (in Melbourne) and now Crane suffering the fate.
In addition Jimmy Anderson overstepped when he had Smith given lbw in Perth only for the Australia captain to go on to make 239.
Crane was still a bright spot for England bowling with increasing control even if his annoying habit of hanging on to the ball when his body does not feel in sync brought jeers from the crowd.
Root was able to bowl him for 22 overs in total at a cost of 77 runs and with the reward of a well-set Khawaja.
Moeen bowled better as well – his 20 overs containing six maidens and 1-74 – for all that he was mauled towards the end of his spell with Mitch Marsh taking 16 off one over.
