England's bowlers staged a plucky early fightback amid an injury scare to captain Joe Root before Australia rallied to build an imposing 371-run lead in the second Ashes Test.
The Australians lost 3-7 in a 10-over span, wobbling to 4-55 early on Sunday's fourth day of play at Adelaide Oval.
But Travis Head (45no from 44 balls) and first-innings centurion Marnus Labuschagne (31no) advanced Australia to 4-134 after the opening session.
English skipper Root was sent for scans after being struck in the testicles when not wearing a protective box while batting during warm-ups.
The world's top-ranked Test batsman was cleared of injury and, after missing the initial 80 minutes of play, returned to the field.
His absence coincided with a bright period for the tourists with the rapid dismissals of nightwatchman Michael Neser (three), opener Marcus Harris (23) and acting captain Steve Smith (six).
England wicketkeeper Jos Buttler's rollercoaster of a Test continued, reeling in two spectacular one-handed catches but dropping another regulation edge.
After Neser was bowled by James Anderson (1-8), Harris fell to Stuart Broad (1-27) two balls later.
A Harris edge flew low to the left of Buttler who, at full stretch, completed a stunning one-handed effort - the second time this Test the Australian opener was outed by a superb catch by the 'keeper.
But next ball, Buttler turfed a nick from Smith when he dived too far to his right and the ball smacked into his wrist.
Smith survived another scare on the following ball when a Broad off-cutter struck him on the pads - the paceman's confident lbw appeal was turned down by umpire Rod Tucker.
England reviewed and replays showed half the ball would have struck off-stump but it was deemed as 'umpire's call' and the not out verdict stood.
Smith failed to cash in, soon after edging a short Ollie Robinson (1-36) delivery down the leg-side.
Buttler - who dropped two basic catching opportunities in the first innings - completed another brilliant one-handed catch, diving low to his left.
Smith's dismissal left Australia 4-55 - including David Warner's run out late Saturday night, the hosts had lost 4-14.
But Head's aggressive cameo, punctuated by six boundaries, restored Australia's dominance.
England face re-writing history to claim a miracle triumph: the highest run chase to win an Adelaide Test is Australia's 6-315 in 1901/02.
